Questions Below Will Be Bases on the Following Study: a Researcher

Multiple Choice

Questions below will be bases on the following study: A researcher wishes to test whether the drug, magnesium pemoline, has any influence on intelligence. Two groups of subjects are randomly selected from the population of Omega University students. Group A is given the magnesium pemoline and then tested on the Stanford-Binet IQ test. Group B is given a placebo and, then, also tested on the Stanford-Binet. Both groups are tested under identical environmental conditions.
-The independent variable in this study is (are) the

A) Stanford-Binet test
B) magnesium pemoline versus the placebo
C) control group
D) IQ scores