WGU D226 – BSNU Capstone Original Practice
Questions & Answers | Bachelor of Science in
Nursing Comprehensive Capstone Study Guide
& Preparation Resource | Evidence-Based
Practice, Healthcare Change Facilitation,
Value-Based Care, Nursing Program Outcomes,
Quality Improvement, Collaborative
Healthcare Projects, Innovation, Clinical
Reasoning & Detailed Rationales
Question 1: A data analyst is tasked with visualizing the relationship between
two continuous variables across multiple categories. Which type of chart
would be MOST appropriate to show both the central tendency and the spread
of the data for each category?
A. Stacked bar chart
B. Pie chart
C. Box plot
D. Scatter plot
CORRECT ANSWER: C. Box plot
Rationale: A box plot (or box-and-whisker plot) is ideal for displaying the distribution of
a continuous variable across different categories. It shows the median (central
tendency), quartiles, and potential outliers (spread) for each category, allowing for easy
comparison. A scatter plot shows relationships between two continuous variables but is
not designed for categorical comparisons of spread.
Question 2: In the context of a database management system (DBMS), what is
the PRIMARY purpose of a foreign key?
A. To uniquely identify each record in a table
B. To enforce data integrity by linking tables
C. To speed up data retrieval operations
D. To define the data type of a column
CORRECT ANSWER: B. To enforce data integrity by linking tables
Rationale: A foreign key is a column or set of columns in one table that refers to the
primary key of another table. Its primary purpose is to enforce referential integrity,
ensuring that relationships between tables remain consistent. Option A describes a
primary key, Option C describes indexing, and Option D is a general data definition task.
Question 3: When performing data cleaning, a data analyst discovers that a
substantial portion of the data is missing. What is a statistically VALID
approach to handling this issue?
,A. Deleting all rows with any missing values
B. Replacing all missing values with the number zero
C. Replacing missing values with the mean or median of that variable
D. Replacing missing values with random values from a normal distribution
CORRECT ANSWER: C. Replacing missing values with the mean or median of
that variable
Rationale: Imputation with the mean or median is a common and statistically valid
method for handling missing data, especially when the data is missing at random and
the proportion of missingness is low. Deleting all rows (A) can lead to significant data
loss and bias. Imputing with zero (B) or random values (D) introduces arbitrary and
often incorrect assumptions, skewing the data's distribution.
Question 4: In a SQL query, which clause is used to filter groups of records
based on a specified condition applied to an aggregate function?
A. WHERE
B. GROUP BY
C. HAVING
D. ORDER BY
CORRECT ANSWER: C. HAVING
Rationale: The HAVING clause is used in conjunction with the GROUP BY clause to
filter groups based on a condition that involves an aggregate function (e.g., HAVING
COUNT(*) > 10). The WHERE clause filters individual rows before grouping, while
ORDER BY sorts the final result set.
Question 5: A business intelligence dashboard should be designed with a
specific user in mind. What is the MOST critical consideration for an
executive-level dashboard?
A. The ability to drill down into granular transaction-level data
B. A clean, high-level summary of key performance indicators (KPIs)
C. Real-time data updates every second
D. The inclusion of complex, multi-step analytical models
CORRECT ANSWER: B. A clean, high-level summary of key performance
indicators (KPIs)
Rationale: Executive dashboards are designed for strategic monitoring. They should
present a concise, at-a-glance summary of the most critical business metrics (KPIs).
While drilling down (A) and real-time data (C) can be features, they are not the primary
focus; the goal is to provide a high-level overview of the health of the business.
Question 6: Which data governance concept ensures that data and its
associated processes comply with legal and regulatory standards?
,A. Data Lineage
B. Data Stewardship
C. Data Compliance
D. Data Quality
CORRECT ANSWER: C. Data Compliance
Rationale: Data compliance specifically refers to the practice of ensuring that the
management and use of data adhere to relevant laws, regulations, and internal policies
(e.g., GDPR, HIPAA). Data lineage (A) tracks the data's journey, stewardship (B) is about
management responsibility, and quality (D) is about accuracy and completeness.
Question 7: What is a key characteristic of an Online Analytical Processing
(OLAP) system as opposed to an Online Transaction Processing (OLTP)
system?
A. OLAP is optimized for high-volume, low-latency write operations.
B. OLAP is designed for complex queries that aggregate large volumes of historical data.
C. OLAP systems are designed to be highly normalized to reduce data redundancy.
D. OLAP systems primarily handle day-to-day business transactions.
CORRECT ANSWER: B. OLAP is designed for complex queries that aggregate
large volumes of historical data.
Rationale: OLAP systems are designed for business intelligence and analytics. They are
optimized for reading and aggregating large datasets to support decision-making. OLTP
systems (A, D) are optimized for transactional operations (insert, update, delete) and are
typically highly normalized (C) to ensure data integrity.
Question 8: A data analyst is creating a presentation to communicate insights
to a non-technical audience. Which approach is MOST effective?
A. Focusing on the technical details of the machine learning algorithm used
B. Presenting raw data tables and complex statistical outputs
C. Using clear, simple language and visualizations to tell a data-driven story
D. Distributing a lengthy, detailed report for them to read independently
CORRECT ANSWER: C. Using clear, simple language and visualizations to tell a
data-driven story
Rationale: For a non-technical audience, the focus should be on the insights and the
story the data tells, not the technical intricacies. Using clear language, avoiding jargon,
and employing compelling visualizations makes the findings accessible, engaging, and
easy to understand.
Question 9: In the context of a SQL database, what is the purpose of a stored
procedure?
A. To define the structure of a table
B. To provide a user-friendly interface for data entry
, C. To encapsulate a pre-compiled set of one or more SQL statements for reuse
D. To enforce data types and constraints on columns
CORRECT ANSWER: C. To encapsulate a pre-compiled set of one or more SQL
statements for reuse
Rationale: A stored procedure is a group of SQL statements that has been compiled and
stored on the database server. It can be executed by name, allowing for code reuse,
improved performance, and centralized business logic. Option A describes a schema
definition, B describes a front-end application, and D describes column constraints.
Question 10: Which type of data visualization is LEAST effective for comparing
parts of a whole?
A. Pie chart
B. Stacked bar chart
C. Tree map
D. Scatter plot
CORRECT ANSWER: D. Scatter plot
Rationale: Scatter plots are designed to show the relationship between two continuous
variables. They do not inherently show how individual parts contribute to a whole. Pie
charts (A), stacked bar charts (B), and tree maps (C) are all effective methods for
visualizing compositional data.
Question 11: The term "Data Warehouse" is BEST described as a:
A. System for storing and managing unstructured data like videos and images.
B. Central repository that stores integrated data from multiple sources for reporting and
analysis.
C. Database designed for high-speed transaction processing.
D. Temporary storage area for data during the ETL process.
CORRECT ANSWER: B. Central repository that stores integrated data from
multiple sources for reporting and analysis.
Rationale: A data warehouse is a centralized repository specifically designed for
analytical queries and reporting. It collects and integrates data from various operational
systems, transforming it for a consistent view of the business. Option A describes a data
lake, C describes an OLTP system, and D describes a staging area.
Question 12: What is the primary goal of data standardization during the data
transformation phase of ETL?
A. To remove all duplicate records from the dataset.
B. To convert data into a consistent, predefined format.
C. To enrich the dataset with additional external information.
D. To validate that the data meets certain business rules.
CORRECT ANSWER: B. To convert data into a consistent, predefined format.
Questions & Answers | Bachelor of Science in
Nursing Comprehensive Capstone Study Guide
& Preparation Resource | Evidence-Based
Practice, Healthcare Change Facilitation,
Value-Based Care, Nursing Program Outcomes,
Quality Improvement, Collaborative
Healthcare Projects, Innovation, Clinical
Reasoning & Detailed Rationales
Question 1: A data analyst is tasked with visualizing the relationship between
two continuous variables across multiple categories. Which type of chart
would be MOST appropriate to show both the central tendency and the spread
of the data for each category?
A. Stacked bar chart
B. Pie chart
C. Box plot
D. Scatter plot
CORRECT ANSWER: C. Box plot
Rationale: A box plot (or box-and-whisker plot) is ideal for displaying the distribution of
a continuous variable across different categories. It shows the median (central
tendency), quartiles, and potential outliers (spread) for each category, allowing for easy
comparison. A scatter plot shows relationships between two continuous variables but is
not designed for categorical comparisons of spread.
Question 2: In the context of a database management system (DBMS), what is
the PRIMARY purpose of a foreign key?
A. To uniquely identify each record in a table
B. To enforce data integrity by linking tables
C. To speed up data retrieval operations
D. To define the data type of a column
CORRECT ANSWER: B. To enforce data integrity by linking tables
Rationale: A foreign key is a column or set of columns in one table that refers to the
primary key of another table. Its primary purpose is to enforce referential integrity,
ensuring that relationships between tables remain consistent. Option A describes a
primary key, Option C describes indexing, and Option D is a general data definition task.
Question 3: When performing data cleaning, a data analyst discovers that a
substantial portion of the data is missing. What is a statistically VALID
approach to handling this issue?
,A. Deleting all rows with any missing values
B. Replacing all missing values with the number zero
C. Replacing missing values with the mean or median of that variable
D. Replacing missing values with random values from a normal distribution
CORRECT ANSWER: C. Replacing missing values with the mean or median of
that variable
Rationale: Imputation with the mean or median is a common and statistically valid
method for handling missing data, especially when the data is missing at random and
the proportion of missingness is low. Deleting all rows (A) can lead to significant data
loss and bias. Imputing with zero (B) or random values (D) introduces arbitrary and
often incorrect assumptions, skewing the data's distribution.
Question 4: In a SQL query, which clause is used to filter groups of records
based on a specified condition applied to an aggregate function?
A. WHERE
B. GROUP BY
C. HAVING
D. ORDER BY
CORRECT ANSWER: C. HAVING
Rationale: The HAVING clause is used in conjunction with the GROUP BY clause to
filter groups based on a condition that involves an aggregate function (e.g., HAVING
COUNT(*) > 10). The WHERE clause filters individual rows before grouping, while
ORDER BY sorts the final result set.
Question 5: A business intelligence dashboard should be designed with a
specific user in mind. What is the MOST critical consideration for an
executive-level dashboard?
A. The ability to drill down into granular transaction-level data
B. A clean, high-level summary of key performance indicators (KPIs)
C. Real-time data updates every second
D. The inclusion of complex, multi-step analytical models
CORRECT ANSWER: B. A clean, high-level summary of key performance
indicators (KPIs)
Rationale: Executive dashboards are designed for strategic monitoring. They should
present a concise, at-a-glance summary of the most critical business metrics (KPIs).
While drilling down (A) and real-time data (C) can be features, they are not the primary
focus; the goal is to provide a high-level overview of the health of the business.
Question 6: Which data governance concept ensures that data and its
associated processes comply with legal and regulatory standards?
,A. Data Lineage
B. Data Stewardship
C. Data Compliance
D. Data Quality
CORRECT ANSWER: C. Data Compliance
Rationale: Data compliance specifically refers to the practice of ensuring that the
management and use of data adhere to relevant laws, regulations, and internal policies
(e.g., GDPR, HIPAA). Data lineage (A) tracks the data's journey, stewardship (B) is about
management responsibility, and quality (D) is about accuracy and completeness.
Question 7: What is a key characteristic of an Online Analytical Processing
(OLAP) system as opposed to an Online Transaction Processing (OLTP)
system?
A. OLAP is optimized for high-volume, low-latency write operations.
B. OLAP is designed for complex queries that aggregate large volumes of historical data.
C. OLAP systems are designed to be highly normalized to reduce data redundancy.
D. OLAP systems primarily handle day-to-day business transactions.
CORRECT ANSWER: B. OLAP is designed for complex queries that aggregate
large volumes of historical data.
Rationale: OLAP systems are designed for business intelligence and analytics. They are
optimized for reading and aggregating large datasets to support decision-making. OLTP
systems (A, D) are optimized for transactional operations (insert, update, delete) and are
typically highly normalized (C) to ensure data integrity.
Question 8: A data analyst is creating a presentation to communicate insights
to a non-technical audience. Which approach is MOST effective?
A. Focusing on the technical details of the machine learning algorithm used
B. Presenting raw data tables and complex statistical outputs
C. Using clear, simple language and visualizations to tell a data-driven story
D. Distributing a lengthy, detailed report for them to read independently
CORRECT ANSWER: C. Using clear, simple language and visualizations to tell a
data-driven story
Rationale: For a non-technical audience, the focus should be on the insights and the
story the data tells, not the technical intricacies. Using clear language, avoiding jargon,
and employing compelling visualizations makes the findings accessible, engaging, and
easy to understand.
Question 9: In the context of a SQL database, what is the purpose of a stored
procedure?
A. To define the structure of a table
B. To provide a user-friendly interface for data entry
, C. To encapsulate a pre-compiled set of one or more SQL statements for reuse
D. To enforce data types and constraints on columns
CORRECT ANSWER: C. To encapsulate a pre-compiled set of one or more SQL
statements for reuse
Rationale: A stored procedure is a group of SQL statements that has been compiled and
stored on the database server. It can be executed by name, allowing for code reuse,
improved performance, and centralized business logic. Option A describes a schema
definition, B describes a front-end application, and D describes column constraints.
Question 10: Which type of data visualization is LEAST effective for comparing
parts of a whole?
A. Pie chart
B. Stacked bar chart
C. Tree map
D. Scatter plot
CORRECT ANSWER: D. Scatter plot
Rationale: Scatter plots are designed to show the relationship between two continuous
variables. They do not inherently show how individual parts contribute to a whole. Pie
charts (A), stacked bar charts (B), and tree maps (C) are all effective methods for
visualizing compositional data.
Question 11: The term "Data Warehouse" is BEST described as a:
A. System for storing and managing unstructured data like videos and images.
B. Central repository that stores integrated data from multiple sources for reporting and
analysis.
C. Database designed for high-speed transaction processing.
D. Temporary storage area for data during the ETL process.
CORRECT ANSWER: B. Central repository that stores integrated data from
multiple sources for reporting and analysis.
Rationale: A data warehouse is a centralized repository specifically designed for
analytical queries and reporting. It collects and integrates data from various operational
systems, transforming it for a consistent view of the business. Option A describes a data
lake, C describes an OLTP system, and D describes a staging area.
Question 12: What is the primary goal of data standardization during the data
transformation phase of ETL?
A. To remove all duplicate records from the dataset.
B. To convert data into a consistent, predefined format.
C. To enrich the dataset with additional external information.
D. To validate that the data meets certain business rules.
CORRECT ANSWER: B. To convert data into a consistent, predefined format.
