Social movements emerge from collective action only when the discontented succeed in establishing:

A) stable membership
B) a "reserve army" of labor
C) an organizational base
D) charismatic leadership and a "reserve army" of labor
E) stable membership and an organizational base

Social movements need stable membership to have a consistent group of people working towards their goals. They also need an organizational base to coordinate and plan their actions effectively. A "reserve army" of labor and charismatic leadership can be helpful, but they are not necessary for the emergence of a social movement. Therefore, the best choice is E, which includes both stable membership and an organizational base as necessary components for the emergence of a social movement.