A; because the narrator is usually a character in a story, who interacts with other characters.
The only preposition in the options available to you is of, so the correct answer is C.
A) and B) are conjunctions.
D) is an adverb.
Seeds begin as a very small object or device, just like our courage. We only need a tiny little seed of courage for it to grow, and once you give that little courage it continues to grow.
