a. violence, death, decay, and burial.
Let's just take a look at some of the words and phrases used in these first two sections of the poem.
"leaves dead", "hectic red", "pestilence-stricken", "dark wintry bed", "corpse". "destroyer", "decaying leaves", "dying year", "closing night", "black rain, and fire, and hail"
All of these words create a very negative mood. The only option that is negative is A so this is the best choice. It should also be noted here that the seasons of Autumn and Winter both signal death. Autumn is the coming of death, while Winter is death. The phrase "dark wintry bed" refers to a person's death bed or coffin.