"There Are Many Assets to Using a Field Study," Said

Multiple Choice

"There are many assets to using a field study," said the graduate student. "First, you're dealing with correlation, so you can draw conclusions about the direction of causality. Second, you have a high degree of control over confounding variables. Third, because you're dealing with a contrived situation, you're bound to have poor external validity. And fourth, your presence might influence the subjects' behavior." Which part of the graduate student's thinking was accurate ?

A) Because it's a correlational study, one can draw conclusions about causality.
B) This type of study affords a high degree of control over confounding variables.
C) Because this type of study is contrived, it will result in poor external validity.
D) The experimenters' presence can influence the subjects' behavior.