In Deciding Which Research Methods to Use, a Researcher Might

In deciding which research methods to use, a researcher might keep in mind that

A) it is never appropriate to use experimental and nonexperimental methods in the same study.
B) nonexperimental methods can still support causal explanations.
C) nonexperimental methods are rarely helpful in science.
D) experimental and nonexperimental methods can be effectively combined in the same study.