In Order to Accurately Determine the Extent to Which Sleep

Multiple Choice

In order to accurately determine the extent to which sleep influences grades, I randomly assign my subjects to one of four groups: 4, 6, 8, or 10 hours of sleep per night. The four groups can be referred to as:

A) the control groups
B) the nominal groups
C) the conditions of the dependent variable
D) the conditions of the independent variable