James Read a Magazine Ad About a Drug That Doctors

James read a magazine ad about a drug that doctors say may help college students perform better on multiple-choice type tests. Being the inquisitive person that he is, James decided to do an experiment to see if the magazine's claims were true. He administered the drug to one of his classes, and gave the other class a placebo. James then tested the students in both groups on material they had recently discussed in class. In this example, what is the experimental group?

A) The students who received the drug
B) The students who received the placebo
C) Test performance
D) The age of the students