One of the Primary Differences Between Experimental Research and Correlational

One of the primary differences between experimental research and correlational research is that:

A) experimental research tends to make more use of naturalistic observation than does correlational research.
B) experimental research tends to use random sampling,while correlational research tends to use random assignment.
C) most experimental research takes place in natural settings,while most correlational research takes place in the laboratory.
D) most experimental research takes place in the laboratory,while most correlational research takes place in natural settings.