I believe "C" is the correct answer, because Connor's friend reminded Connor that the car's gas gauge is broken, meaning that the car would break down.
The answer to this question is A!
That would probably the way the sentence flows and the tone
Montresor is considered an unreliable narrator because his opinion of Fortunato is biased. Montresor feels greatly wronged by Fortunato, but the exact wrongdoing that Fortunato has committed is never clearly mentioned in the story.