How do lines 13- 15 the sun has long been set

this would be in the imperative mood. it is a category of verb forms that are used to express orders,instructions,commands or requests.

the correct answer would be:  

a. adverb phrase

the answer is option 1

explanation:

obama was told in early july 2004 that he was chosen to deliver the address, and he largely wrote the speech himself, with later edits from the kerry presidential campaign.