Answer:
The options are
a.
The group that drinks water
b.
The performance on the exam
c.
The group that has coffee
d.
There is no experimental group as this is a case study
The answer is c.The group that has coffee
Step-by-step explanation:
Dr. Turner is said to form the hypothesis that ingesting caffeine prior to an exam will improve exam performance. In a study, she gives half of the participants coffee and the other half water. It is known that tea contains caffeine. The investigation and experiment is centered around Caffeine which makes the group that has coffee the experimental group while the people who took water will be the control group which will be used in comparisons with the results gotten from the experimental group.