A Psychologist Wants to Collect Some Information from Individuals Who

A psychologist wants to collect some information from individuals who have been diagnosed as suffering either acute stress disorder or posttraumatic stress disorder. Which of the following could provide the best indication of the presence of certain symptoms in these individuals?

A) They are asked to keep track of their calorie intake for a period of two months.
B) They are asked to fill out a questionnaire asking for basic demographic information.
C) They are videotaped as they wait to be interviewed and react to an expected loud noise.
D) They are asked to proceed to another building on campus and their speed of walking is measured.