B is the only correct answer.
A should be "yours"
C should be "its"
D should be "hers"
Answer is B! Therefore the sentence would be "in MLA format, use italics throughout your essay for the titles of LONGER works.
You shouldn’t include the fourth one
- Some fringing reefs create atolls.
I believe that the message the author is trying to convey in this excerpt is that humans need to take action to end further destruction of the natural environment, because if they don't, more and more species will disappear.