Answer:
B. the mental condition of the inhabitants of the house
Step-by-step explanation:
As stated in the excerpt from "The Fall of the House of Usher," by Edgar Allan Poe, the visible abandonment of the house reflects the intellectual and physical deterioration of the Ushers. In that respect, the narrator makes reference to the neglected walls, to the uncomfortable and outdated furniture, to the poor condition of the books and to the musical instruments, which give him a lifeless impression. Besides, he also mentions the persistent smell and the darkness spread throughout the house.