The Ways in Which Evaluators Expand on the Pretest/posttest Design

Multiple Choice

The ways in which evaluators expand on the pretest/posttest design in order to control for threats to internal validity include the following EXCEPT for

A) increasing the size of the sample to reduce Type I and Type II errors.
B) observing the participants at additional times before and after the intervention.
C) observing additional people who have not received the program.
D) using a variety of variables, some expected to be affected by the program, some not.