Incomplete sentence is the answer
In Edgar Allan Poe's short story The Fall of the House of Usher, Roderick Usher writes his childhood friend a letter informing his friend about his illness. Roderick's sister is also ill and he is worried about her, as well. He developed an abnormal behavior and started to think that the mansion they live controls him and it will eventually bring his end. As we can observe, Usher is physically and mentally ill and wants a help from his childhood friend. The correct answer is C.
Answer:
This all depends on context, but in general:
Neutral: Generally having a middle ground opinion rather than being on an extreme side.
Positive: Usually refers to one's attitude, optimism. Can also mean certainty.
Negative: Not positive, could be referring to pessimism or seeing the bad side of things.