What do naturalistic observations,case studies,and surveys all have in common

A)  They involve manipulating the variables of interest in the study. 
B)  They show cause-and-effect relationships. 
C)  They take place in an artificial setting. 
D)  They involve describing behaviour.

Naturalistic observations, case studies, and surveys all involve describing behavior. Naturalistic observations involve observing behavior in a natural setting without any manipulation of variables, case studies involve in-depth descriptions of individual cases, and surveys involve collecting self-report data on behavior and attitudes. None of these methods show cause-and-effect relationships, and they do not take place in an artificial setting as they aim to describe behavior in real-life situations.