AP PSYCHOLOGY MASTER EXAM PREP BUNDLE: 200 VERIFIED
PRACTICE QUESTIONS WITH DETAILED ANSWER RATIONALES
1. Dr. Ramirez is conducting a study to determine whether a new anti-
anxiety medication reduces reported stress levels in college students.
She randomly assigns participants to either a medication group or a
placebo group. In this study, the independent variable is:
A. The reported stress levels of the participants
B. The anti-anxiety medication
C. The college students
D. The placebo group
Correct Answer: B
Rationale: The independent variable is the variable that the researcher
manipulates. In this study, Dr. Ramirez manipulates whether
participants receive the medication or a placebo. The reported stress
levels (A) are the dependent variable, the college students (C) are the
population, and the placebo group (D) is a control condition, not the
independent variable itself.
2. A researcher wants to examine the relationship between hours
spent studying and exam performance. Which research method would
be most appropriate for this goal?
A. Experiment
B. Case study
C. Correlational study
D. Naturalistic observation
,Correct Answer: C
Rationale: A correlational study is used to examine the relationship
between two variables without manipulating them. An experiment (A)
would require manipulating study time, which may be unethical or
impractical. A case study (B) examines a single individual in depth, and
naturalistic observation (D) involves observing behavior in a natural
setting without manipulation.
3. Which of the following best describes the purpose of a control
group in an experiment?
A. To provide a baseline for comparison against the experimental group
B. To ensure that all participants receive the treatment
C. To increase the sample size of the study
D. To eliminate the need for random assignment
Correct Answer: A
Rationale: The control group serves as a baseline condition that does
not receive the experimental treatment, allowing researchers to
compare the effects of the treatment. Option B is incorrect because the
control group does not receive the treatment. Option C is incorrect
because increasing sample size is not the primary purpose of a control
group. Option D is incorrect because random assignment is still
necessary to minimize bias.
4. A psychologist wants to ensure that neither the participants nor the
researchers know which participants are in the experimental group
and which are in the control group. This is known as a:
A. Single-blind study
B. Double-blind study
,C. Placebo effect
D. Confounding variable
Correct Answer: B
Rationale: A double-blind study is one in which both the participants
and the researchers are unaware of the group assignments, reducing
bias. A single-blind study (A) occurs when only the participants are
unaware. The placebo effect (C) refers to a participant's expectations
influencing results. A confounding variable (D) is an extraneous variable
that may affect the results.
5. Which of the following correlation coefficients indicates the
strongest relationship between two variables?
A. +0.45
B. -0.82
C. +0.10
D. -0.25
Correct Answer: B
Rationale: The strength of a correlation is determined by the absolute
value of the coefficient, regardless of the sign. -0.82 has the largest
absolute value, indicating the strongest relationship. The positive or
negative sign indicates the direction of the relationship, not its strength.
6. A researcher finds that as ice cream sales increase, rates of
drowning also increase. Which of the following is the most likely
explanation for this correlation?
A. Eating ice cream causes people to swim more often
B. Drowning causes people to eat more ice cream
C. A third variable, such as temperature, causes both to increase
D. The correlation is spurious and cannot be explained
, Correct Answer: C
Rationale: Correlation does not imply causation. A third variable, such
as warm weather, could explain why both ice cream sales and drowning
rates increase simultaneously. Options A and B incorrectly assume
causation. Option D is incorrect because the correlation can be
explained by a confounding variable.
7. In a normal distribution, approximately what percentage of scores
falls within one standard deviation of the mean?
A. 50%
B. 68%
C. 95%
D. 99%
Correct Answer: B
Rationale: In a normal distribution, approximately 68% of scores fall
within one standard deviation of the mean. Approximately 95% fall
within two standard deviations (C), and approximately 99.7% fall within
three standard deviations (D). Option A is incorrect because 50% would
represent scores below the mean only.
8. A psychologist is studying the effects of sleep deprivation on
reaction time. She measures reaction time in milliseconds. Reaction
time is an example of:
A. Ordinal data
B. Nominal data
C. Interval data
D. Ratio data
Correct Answer: D
Rationale: Ratio data has a true zero point, meaning a reaction time of
PRACTICE QUESTIONS WITH DETAILED ANSWER RATIONALES
1. Dr. Ramirez is conducting a study to determine whether a new anti-
anxiety medication reduces reported stress levels in college students.
She randomly assigns participants to either a medication group or a
placebo group. In this study, the independent variable is:
A. The reported stress levels of the participants
B. The anti-anxiety medication
C. The college students
D. The placebo group
Correct Answer: B
Rationale: The independent variable is the variable that the researcher
manipulates. In this study, Dr. Ramirez manipulates whether
participants receive the medication or a placebo. The reported stress
levels (A) are the dependent variable, the college students (C) are the
population, and the placebo group (D) is a control condition, not the
independent variable itself.
2. A researcher wants to examine the relationship between hours
spent studying and exam performance. Which research method would
be most appropriate for this goal?
A. Experiment
B. Case study
C. Correlational study
D. Naturalistic observation
,Correct Answer: C
Rationale: A correlational study is used to examine the relationship
between two variables without manipulating them. An experiment (A)
would require manipulating study time, which may be unethical or
impractical. A case study (B) examines a single individual in depth, and
naturalistic observation (D) involves observing behavior in a natural
setting without manipulation.
3. Which of the following best describes the purpose of a control
group in an experiment?
A. To provide a baseline for comparison against the experimental group
B. To ensure that all participants receive the treatment
C. To increase the sample size of the study
D. To eliminate the need for random assignment
Correct Answer: A
Rationale: The control group serves as a baseline condition that does
not receive the experimental treatment, allowing researchers to
compare the effects of the treatment. Option B is incorrect because the
control group does not receive the treatment. Option C is incorrect
because increasing sample size is not the primary purpose of a control
group. Option D is incorrect because random assignment is still
necessary to minimize bias.
4. A psychologist wants to ensure that neither the participants nor the
researchers know which participants are in the experimental group
and which are in the control group. This is known as a:
A. Single-blind study
B. Double-blind study
,C. Placebo effect
D. Confounding variable
Correct Answer: B
Rationale: A double-blind study is one in which both the participants
and the researchers are unaware of the group assignments, reducing
bias. A single-blind study (A) occurs when only the participants are
unaware. The placebo effect (C) refers to a participant's expectations
influencing results. A confounding variable (D) is an extraneous variable
that may affect the results.
5. Which of the following correlation coefficients indicates the
strongest relationship between two variables?
A. +0.45
B. -0.82
C. +0.10
D. -0.25
Correct Answer: B
Rationale: The strength of a correlation is determined by the absolute
value of the coefficient, regardless of the sign. -0.82 has the largest
absolute value, indicating the strongest relationship. The positive or
negative sign indicates the direction of the relationship, not its strength.
6. A researcher finds that as ice cream sales increase, rates of
drowning also increase. Which of the following is the most likely
explanation for this correlation?
A. Eating ice cream causes people to swim more often
B. Drowning causes people to eat more ice cream
C. A third variable, such as temperature, causes both to increase
D. The correlation is spurious and cannot be explained
, Correct Answer: C
Rationale: Correlation does not imply causation. A third variable, such
as warm weather, could explain why both ice cream sales and drowning
rates increase simultaneously. Options A and B incorrectly assume
causation. Option D is incorrect because the correlation can be
explained by a confounding variable.
7. In a normal distribution, approximately what percentage of scores
falls within one standard deviation of the mean?
A. 50%
B. 68%
C. 95%
D. 99%
Correct Answer: B
Rationale: In a normal distribution, approximately 68% of scores fall
within one standard deviation of the mean. Approximately 95% fall
within two standard deviations (C), and approximately 99.7% fall within
three standard deviations (D). Option A is incorrect because 50% would
represent scores below the mean only.
8. A psychologist is studying the effects of sleep deprivation on
reaction time. She measures reaction time in milliseconds. Reaction
time is an example of:
A. Ordinal data
B. Nominal data
C. Interval data
D. Ratio data
Correct Answer: D
Rationale: Ratio data has a true zero point, meaning a reaction time of
