Imperialism is the growth or building if an empire. Some reasons for imperialism is for more land=money=power, refuling stations, military bases, other nations are doing it, and markets.
The Americans hostility towards the clergy, adherents, and the Catholic Church during the 1800s was rooted to their desires to maintain the white, Protestant nation. The reform even led to religious discrimination and violence. Therefore, the answer to this question is most probably letter D.
Because the price of Bread skyrocketed.
The term for the significant growth in population following WWII is the "baby boom." We also now refer to those people as "baby boomers"