The best way to combine both of the sentences would be: Soldiers and civilians began using the nickname Uncle Sam to refer to the United States.
The answer is B. Metaphore
Here is why:
a figure of speech in which a word or phrase is applied to an object or action to which it is not literally applicable.
"“I had fallen through a trapdoor of depression,”
This is all pretty subjective because one person may have one type of a feeling about this extract, and the other person may have completely different feelings.
For me personally, this simile creates a gloomy mood. The simile 'the hollow halo it was in was like an icy crystal cup' creates a gloomy and cold atmosphere in my opinion.
Conflict is not one of the main five of a plot
