Which of the Following Statements Regarding the Differences Between Experimental

Which of the following statements regarding the differences between experimental and correlational research is FALSE?

A) In experimental research, at least one variable is measured, while in correlational research, all variables are measured.
B) Correlational research makes more use of random assignment than does experimental research.
C) Correlational researchers are not able to keep extraneous factors constant the way that experimental researchers can.
D) Experimental research involves manipulating at least one variable, whereas correlational research often uses methods such as surveys and naturalistic observations.