Melvin and Leigh Are Interviewing Students at Their Campus to Determine

Multiple Choice

Melvin and Leigh are interviewing students at their campus to determine if the students agree or disagree with a proposed policy change. Melvin believes the proposed policy change is a good idea, but Leigh believes the change will be bad for students. Nearly all the students who Melvin interviewed supported the policy change, but nearly all the students who Leigh interviewed disapproved of the change. The differences in the results illustrate the potential impact of ​

A) the placebo effect.
B) double-blind research studies. ​
C) confounded dependent variables. ​
D) experimenter bias. ​