Answer:
D. That he has no morals and might possibly be insane
Step-by-step explanation:
According to the passage from "The Black Cat", it is described by the narrator that he murdered someone and is attempting to conceal it. He does not want to be implicated and seen by the neighbors while he's moving the dead body.
The businesslike tone of this passage help the reader infer that the narrator has no morals and might possibly be insane.