If Real Estate Agents in St

Multiple Choice

If real estate agents in St.Louis are offered the chance to attend a voluntary training session on Missouri State Law,the fact that agents who are having difficulty making enough sales to have sufficient income means that they are more likely to attend these training sessions is an example of which type of extraneous variable?

A) Maturation
B) Testing effects
C) Selection bias
D) History
E) Regression to the Mean