Whyte's study of "corner gangs"

A) experimentally manipulated norms.
B) used structured observations.
C) made use of participant observation.
D) was a self-report study.

Whyte's study of "corner gangs" involved participant observation, where the researcher becomes part of the group being studied and observes their behavior and social interactions. While the study did include some structured observations and interviews, the primary method used was participant observation. The study did not experimentally manipulate norms, nor did it rely solely on self-report measures.