Name the two most important components of the Columbian Exchange and why?

I'm not really sure but this is what I know

Explanation:

The Columbian exchange, also known as the Columbian interchange, named after Christopher Columbus, was the widespread transfer of plants, animals, culture, human populations, technology, diseases, and ideas between the Americas, West Africa, and the Old World in the 15th and 16th centuries.

New foods for both Europe and the Americas was a major part of the Columbian Exchange. The Americas provided such new foods as corn, the potato, the tomato, peppers, pumpkins, squash, pineapples, cacao beans (for chocolate) and the sweet potato. Also, such animals as turkeys provided a new food source for Europeans.

after the roman empire, the catholic church began to unify by taking on many duties of a government.

answer: the correct answer is d. a christian revivalist movement in the u.s. during the early 19th century

explanation: the second great awakening was lead by the preachers of baptist and methodist congregations in order to gain support for the protestant religion from the 1790's to 1840's