A sustained challenge to those in power put forth by individuals, acting in concert with others, who have been excluded from the political process or who consider themselves political outsiders is known as:

Social Movement

Explanation:

A social Movement is a group of diffusely organized people or organizations striving toward a common goal relating to human society or social change, or the organized activities of such a group. It is a collectively acting with some continuity to promote or resist a change in the society or group of which it is a part.

the answer to your question is,

d. when a child was born.

-mabel < 3

answer; pentagon papers, vietnam draft-resistor, james dean, american revolution;