This threat to internal validity refers to problems in how groups were formed such that the

groups are not equal before the experiment.

A) selection B) maturation C) testing D) history

A

Psychology

You might also like to view...

How does the SEM work

What will be an ideal response?

Psychology

Studies that show how personality traits are strongly influenced by genes also prove that environments have very little influence in the development of personality traits

Indicate whether the statement is true or false.

Psychology