I would say D) Because swimming races are won by inches, the new suits can make a difference. It's joining a statement and a reason for the statement.
2, 4, and 5 have to be the answer by process of elimination
Edit: 4 "he followed out his original design," is incorrect but 2 "Endowed with commonsense, as massive and hard as blocks of granite" and 5 "On the score of delicacy, or any scrupulousness which a finer sensibility might have taught him, the Colonel, like most of his breed and generation, was impenetrable." are.
The theme of this is the idea that all the actions which you do to try to determine the aesthetic of a poem is vain if you in any way feel the need to manipulate it or even try to interpret it -- it is its own being. It is a complex, incalculable demonstration of beauty.
