Multiple Choice
A researcher is testing the hypothesis that an herbal supplement improves concentration. Before taking a concentration test, the first group gets the supplement. Which of the following reflects the highest quality research design for this hypothesis?
A) A second group gets nothing. A computer system tracks which participants get supplements.
B) A second group gets nothing. The person giving the concentration test keeps track of which participants get supplements.
C) A second group gets an identical pill but without the supplement. The person giving the concentration test keeps track of who gets which pill.
D) A second group gets an identical pill but without the supplement. A computer system tracks who gets which pill.
Correct Answer:

Verified
Correct Answer:
Verified
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