B and D are the best answers. A, B, and D are all actual answers. Refer to your textbook for context on which of the three would satisfy your teacher most.
It is d because of the more immigrants
The idea that was the most divisive between the patriots and loyalists in the years leading up to the Revolution was whether or not Britain's taxes were excessive or not. And, whether the colonies deserved representation in British Parliament.
Well, once the Americas were discovered and the colonist found that the soil was agreeable to grow different crops such as tobacco and cotton the colonists realized that they needed people to pick the crops. Originally indentured servants did the hard labor but then when they found that they could get labor by trading goods with African tribal leaders they resorted to importing Africans to the Americas as labor. The tribes in Africa were constantly fighting and whichever side won the losers became the slaves of the winning tribe. However, as Europeans brought valuable things to the continent of Africa such as weapons, salt, gold, and other things the leaders of the winning tribe would give their slaves to the Europeans. There were cases when Blacks captured other Blacks in Africa for the sole purpose of giving them to the European traders. Hopefully this helps. If you haven't see the movie La Amistad, it will explain in more detail what I have written. I learned a lot from that movie. I must warn you the first 5 to 10 minutes are a bit gory. I had a hard time watching that part.
The Revolution also unleashed powerful political, social, and economic forces that would transform the post-Revolution politics and society, including increased participation in politics and governance, the legal institutionalization of religious toleration, and the growth and diffusion of the population