It is an Adverb. Adverb modifies and functions like an adjective.
I would say the most logical one to put in a fictional narrative would be the second one about the sun mocking the moon. personification is seen usually in fictional works, so it would make more sense :) hope this helps!
I read that book.What do you need help with?
Not too sure, but I think it’s the last option: This is a complex sentence because it joins an independent clause with a dependent clause
