Which Statement Best Captures the Basic Idea Underlying the Experimental

Multiple Choice

Which statement best captures the basic idea underlying the experimental method?

A) Sample participants carefully observe their behavior and report the results.
B) One should describe and measure behavior under a wide variety of uncontrolled conditions.
C) It is important to manipulate an independent variable to look for an effect on a dependent variable.
D) A researcher manipulates a dependent variable to look for an effect on an independent variable.