WGU C949 Data Structures and Algorithms – Final Exam
Comprehensive Practice Examination
120 Questions with Verified Answers and Detailed
Rationales
SECTION 1: FOUNDATIONAL CONCEPTS & DATA TYPES
Questions 1–20
Question 1
Which of the following best defines a data structure?
A) A collection of algorithms used for sorting data
B) A specific way to organize and store data for efficient access and modification
C) A programming language feature that enables recursion
D) A hardware component that stores data permanently
Correct Answer: B
Rationale: A data structure is a specialized format for organizing, processing, retrieving, and storing data.
It is not limited to sorting, recursion, or hardware components. Data structures provide the means to
manage large amounts of data efficiently for various operations.
Question 2
What is the primary purpose of an algorithm?
,A) To allocate memory for variables
B) To provide a step-by-step procedure for solving a problem or performing a computation
C) To define the syntax of a programming language
D) To manage network connections
Correct Answer: B
Rationale: An algorithm is a finite sequence of well-defined instructions to solve a specific problem. It is
not responsible for memory allocation, syntax definition, or network management—these are handled
by other components of a computing system.
Question 3
Which term refers to a template for creating an object?
A) Method
B) Algorithm
C) Class
D) Variable
Correct Answer: C
Rationale: A class is a blueprint or template from which objects are created. It defines the properties
(attributes) and behaviors (methods) that objects of that type will have. Methods are behaviors,
algorithms are procedures, and variables store data.
Question 4
Which characteristic of an algorithm is independent in nature?
A) It must be written in a specific programming language
B) It must use a specific data structure
,C) It is agnostic to any specific programming language or platform
D) It must run on a specific operating system
Correct Answer: C
Rationale: An algorithm should be described in a way that is not tied to a specific programming language
or implementation, making it language-agnostic. Algorithms are conceptual solutions that can be
implemented in any programming language on any platform.
Question 5
What is referred to as a data structure that stores subitems (fields)?
A) Array
B) Record
C) List
D) Stack
Correct Answer: B
Rationale: A record (or struct) is a data structure that groups together related data items (fields) under a
single name. Arrays store elements of the same type in contiguous memory, lists are ordered
collections, and stacks follow LIFO ordering.
Question 6
Which data type is appropriate for this array? a = ["AF", "71", "BC", "157", "BA", "253"]
A) Byte
B) Char
C) Short
D) String
, Correct Answer: D
Rationale: The array contains alphanumeric sequences that include both letters and numbers. These are
best represented as strings, as they are not purely numeric (Byte, Short) nor single characters (Char).
Question 7
What is the time complexity of accessing an element by index in an array?
A) O(1)
B) O(log n)
C) O(n)
D) O(n²)
Correct Answer: A
Rationale: Arrays provide constant-time access to elements when the index is known. This is because
array elements are stored in contiguous memory locations, allowing direct calculation of the memory
address using the base address and index offset.
Question 8
Which of the following Big O notations represents the fastest-growing time complexity?
A) O(1)
B) O(log n)
C) O(n)
D) O(n²)
Correct Answer: D
Comprehensive Practice Examination
120 Questions with Verified Answers and Detailed
Rationales
SECTION 1: FOUNDATIONAL CONCEPTS & DATA TYPES
Questions 1–20
Question 1
Which of the following best defines a data structure?
A) A collection of algorithms used for sorting data
B) A specific way to organize and store data for efficient access and modification
C) A programming language feature that enables recursion
D) A hardware component that stores data permanently
Correct Answer: B
Rationale: A data structure is a specialized format for organizing, processing, retrieving, and storing data.
It is not limited to sorting, recursion, or hardware components. Data structures provide the means to
manage large amounts of data efficiently for various operations.
Question 2
What is the primary purpose of an algorithm?
,A) To allocate memory for variables
B) To provide a step-by-step procedure for solving a problem or performing a computation
C) To define the syntax of a programming language
D) To manage network connections
Correct Answer: B
Rationale: An algorithm is a finite sequence of well-defined instructions to solve a specific problem. It is
not responsible for memory allocation, syntax definition, or network management—these are handled
by other components of a computing system.
Question 3
Which term refers to a template for creating an object?
A) Method
B) Algorithm
C) Class
D) Variable
Correct Answer: C
Rationale: A class is a blueprint or template from which objects are created. It defines the properties
(attributes) and behaviors (methods) that objects of that type will have. Methods are behaviors,
algorithms are procedures, and variables store data.
Question 4
Which characteristic of an algorithm is independent in nature?
A) It must be written in a specific programming language
B) It must use a specific data structure
,C) It is agnostic to any specific programming language or platform
D) It must run on a specific operating system
Correct Answer: C
Rationale: An algorithm should be described in a way that is not tied to a specific programming language
or implementation, making it language-agnostic. Algorithms are conceptual solutions that can be
implemented in any programming language on any platform.
Question 5
What is referred to as a data structure that stores subitems (fields)?
A) Array
B) Record
C) List
D) Stack
Correct Answer: B
Rationale: A record (or struct) is a data structure that groups together related data items (fields) under a
single name. Arrays store elements of the same type in contiguous memory, lists are ordered
collections, and stacks follow LIFO ordering.
Question 6
Which data type is appropriate for this array? a = ["AF", "71", "BC", "157", "BA", "253"]
A) Byte
B) Char
C) Short
D) String
, Correct Answer: D
Rationale: The array contains alphanumeric sequences that include both letters and numbers. These are
best represented as strings, as they are not purely numeric (Byte, Short) nor single characters (Char).
Question 7
What is the time complexity of accessing an element by index in an array?
A) O(1)
B) O(log n)
C) O(n)
D) O(n²)
Correct Answer: A
Rationale: Arrays provide constant-time access to elements when the index is known. This is because
array elements are stored in contiguous memory locations, allowing direct calculation of the memory
address using the base address and index offset.
Question 8
Which of the following Big O notations represents the fastest-growing time complexity?
A) O(1)
B) O(log n)
C) O(n)
D) O(n²)
Correct Answer: D
