Psychologists carefully control conditions and measure behavior by

Psychologists carefully control conditions and measure behavior by carefully analyzing human behavior at different situations. This can be done as a procedure while performing the the experiment research.

Psychologists are the expert persons who can explain and control mental behavior of the patient. dekhen ki or a person who is going through mental stress or depression. They have their own strategy and procedure for curing the patient. When a person is mentally not stable, through his or her action we can get to know about it.  

answer; i believe that the correct answer is (b) is a factor associated with physical activity and heart disease;

answer; i believe the correct answer is ( mediation);