Answer:
The correct answer is letter "A": nonequivalent group.
Explanation:
While conducting studies, nonequivalent groups are those where the target audience is not selected randomly. Instead, the participants are chosen generating another group represented by all those individuals who match the research criteria but, because of a reason, were not selected.
There are different types of nonequivalent groups such as posttest only nonequivalent groups or pretest-posttest nonequivalent groups, for instance.
