Choice A has an incorrect comma after brown. It should be absent to sound correct. To hear the difference in your head think "brown paper bag" versus "brown....paper bag".
Choice B lacks a comma after sunscreen.
Choice C correctly places commas when saying "not Karmen". This seems to be the correct answer.
Choice D is incorrect, it fail to put a comma after "a star on the swim team".
Choice C is the correct choice.
Answer:
I think it would be A. Leave it as is, because the other answers don't sound right, or don't have any commas.
Hope this helped! :)
An ailment is a disease that is very common but not serious
