Answer:
The way this design supports the conclusion is that there is a correlation between the exercise and the results of the test.
Explanation:
To understand this answer we need to analyze the research method. First of all, he had a research question similar to: does aerobic exercise helps people have healthier mental health? then he reunited one control group and one experimental group. The variables were the results of the instrument and the aerobic exercise. Obtaining that the group that didn't perform exercise had lower mental health than the group who did exercise.