When people engage in contentious politics outside the mainstream political process to address specific social issues such as inequality or injustice in an effort to transform cultural patterns or government policies, this is defined as a:

A. cultural enterprise.
B. crusade.
C. public initiative.
D. social movement.
E. cause célèbre.

D. social movement

Explanation:

A social movement is an organized effort by a group of people usually large in size and that falls out of the mainstream politics to tackle a particular social or political issue. This group of people in this way try to show their disapproval of a particular political or social issue. is Social movements are a type of group action and may involve individuals or organizations.