For a Simple Experiment, Which of the Following Is True

Multiple Choice

For a simple experiment, which of the following is true?

A) As a null hypothesis, assume that the two groups represent different populations.
B) Apply the dependent variable to both groups and then measure the changes in the independent variable.
C) Find the probability that the two samples are from different populations by using a t distribution.
D) Treat both groups exactly alike except for one thing.