In Trying to Understand the Evacuation of the World Trade

In trying to understand the evacuation of the World Trade Center when it was first bombed in 1993, B. E. Aguirre, Dennis Wenger, and Gabriela Vigo argue that the more "the search for meaning in the milling process focuses upon defining the situation as serious, the quicker should be the mobilization of people and the initiation of collective behavior." What type of theory are they using to make this prediction?

A) technological determinism
B) emergent norm theory
C) contagion theory
D) cultural diffusion
E) historical materialism