I would go with D) It helps show the author's voice because the author is saying that the person is making him sad at night so u could say he is opening his feelings.
Paying for it
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If your using it in a describing sense (adjective) , integral would mean its needed to make something complete .
In the story Odysseus' men after a terrible storm slay the sun god's heifers in order to not die of starvation. the only survivor was Odysseus.
