What was the counter-reformation?
a.) a series of actions by the protestant church intended to separate the church and the state
b.) a series of actions by the catholic church intended to spread and defend the catholic faith
c.) a movement led by martin luther with the goal of reforming the church
d.) a movement led by the catholic church with one goal of electing a new pope

B.) A series of actions by the Catholic Church intended to spread and defend the catholic faith

The Counter-Reformation (1545-1648), as a movement of reform within the Roman Catholic Church, started as a reaction to the Protestant Reformation.

Mainly it sought to reaffirm principles to defend from Protestants' opposition (Pope’s authority, veneration of the saints, etc.), to eliminate some of the abuses the protestants criticized like the sale of indulgences for the remission of sin, to spread the Catholic faith and to get church members to remain loyal to it.

i believe it would be a single seller : )