A Difference Between Crowd Collective Action and Mass Collective Action

A difference between crowd collective action and mass collective action is that:

A) crowd collective action involves fewer than 100 people, while mass collective action involves more than 100 people.
B) crowd collective action has clearly defined goals, while mass collective action makes them up is it goes along.
C) crowd collective action is violent, while mass collective action is peaceful.
D) crowd collective action involves face-to-face interactions with other group members, while mass collective action can use media to tie people together.