Answer:
d.
Explanation:
According to my research on the scientific method, I can say that based on the information provided within the question in this experiment the control group shouldn’t be exposed to music, but otherwise treated the same as the experimental groups. This is because in an experiment a control group is a group that the researcher control every aspect of, this group needs to be treated exactly like all the other groups but with the absence of the variable that is being tested on the other groups. Which in this experiment would be the music.
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