What effect does using the first-person narrative have in Edgar Allan Poe’s short stories “The Cask of Amontillado” and “The Black Cat”?

A. It makes readers sympathize with the narrators and their circumstances.
B. It gives readers an understanding of why the narrators were forced to commit murder.
C. It gives readers an understanding of the deranged minds of the narrators and their motivations.
D. It makes readers aware of the relationships between the narrator and the other characters.