I think its gerund phrase but im not 100% sure
Answer:
Choice C! :)
Explanation:
Appositives are groups of words that rename the noun next to it. You hear them all the time in normal conversations. It's easiest to identify them by seeing which flows best and which has the correct comma placement.
Choice D is wrong because 'very badly' is acting as an adverb phrase.
Choice B is wrong because it breaks up the sentence.
Choice A is wrong because 'the main one in town' does not rename the post office.
