You can use a little trick here: interrogative is essentually a question! and here one of the sentences has a question mark at the end. Is it a question? it is! so it's the correct answer! (also there are no other questions here).
Your answer would be D) Simile. This is because the clause compares the loneliness to a cloud, and similes are used to compare things, like "The food was as hot as the sun" or "The school was like a zoo".
