Which of the Following Is True of the Sociological Study

Which of the following is true of the sociological study of crowds and collective behavior more generally?

A) Sociologists have very recently become interested in the behavior of people in crowds.
B) Sociologists originally focused on the evolution of crowds into social movements.
C) More recently, sociologists have focused on the herdlike behavior of crowds.
D) There are three principal sociological theories used to study collective behavior: contagion theories, emergent norm theories, and value-added theories.