I just took the quiz! The answer is "B"
The reference to the "booming drums of the regiment" indicates that this section of the poem depicts a battle and takes place during a time when military drums were still used during conflict.
B. Does not. A prefix won't change the root word. If you take a prefix off of a root word the root word will always stay the same.
The answer is B...knowing about her heart condition develops her character, this in turn makes her later death believable because she has been characterized as someone with a fragile heart.