Forty people are divided into two groups. One group is exposed to atonal classical music The other is not. After one month both groups are questioned about their ability to remember random phrases

Question

.Is the study an observational study or an​ experiment?
A.
The study is an experiment because the study examines individuals in a​ sample, but does not try to influence the variable of interest.
B.
The study is an experiment

because the researchers control one variable to determine

the effect on the response variable.
C.
The study is an observational study because the researchers control one variable to determine the effect on the response variable.
D.

Answer 1

The study is an experiment because the researchers control one variable to determine the effect on the response variable.