Answer:
The answer is D: They were close friends.
Henry David Thoreau and Ralph Waldo Emerson were fellow transcendentalists and probably two of the most influential authors in this movement. However, there was never rivalry between them - Emerson was David's mentor and a very close friend. The two of them significantly influenced not only each other's lives, but also careers. They spent some time living together at Emerson's home in 1840s, which strengthened their honest friendship even more.
