Question

question
brian researched how a persons intelligence quotient (iq) is affected by exercise. first, people took an iq test. then, over 2 months, they did different amounts of exercise. then, brian gave them a second iq test.
what is the response variable in this experiment?
select the correct answer below:
○ the number of people in the study
○ the first iq test score
○ the amount of exercise the people do
○ the change in iq score from the first to second test

Explanation:

A response variable is what is being measured or observed to see the effect of the explanatory variable. Here, the explanatory variable is the amount of exercise. The response variable should reflect the outcome related to IQ affected by exercise. The change in IQ score from first to second test shows how IQ was affected by exercise, while the other options are either not the outcome (like number of people, first IQ score) or the explanatory variable (amount of exercise).

Answer:

D. The change in IQ score from the first to second test