In a Correlational Study, the Researcher _______; in an Experiment

In a correlational study, the researcher _______; in an experiment the researcher _______.

A) is limited in what she can study by practical and ethical constraints; examines the full range of two variables
B) considers both independent and dependent variables; can draw causal conclusions
C) may be worried about random selection; compares the responses of two or more groups of participants
D) must use random assignment to condition; manipulates a variable and measures another variable