How many of us are outcasts?
(NF fans)

Generally spontaneous human combustion is something that still bewilders some, human combustion happens very rarely and doesn't affect the surrounding areas, so unless you want to set your self on fire, human combustion will remain spontaneous and very rare.

Iwould go with write exactly two extra paragraphs to point out additional information. but the keyword "exactly" throws me off. leads me to believe it's d. go with your gut feeling. either "write exactly two extra paragraphs" or "none of these".