First off the answer for this catchy question is the second sentence which by the way it's intentionally hidden, has an intended punctuation error or a non-intended briefly slip because of the comma that should never be written down there, in other words:
# 1 sentence: The author's claim is that (of) a diet rich in vegetables/(Wrong option since it never ends up saying the sentence's objective nor the rest; so it's incomplete)
# 2 sentence: Whole grains(,) and beans can help prevent cancer.(Correct option)
Well, it's actually pretty simple. You see, the words hour and spring are often used with various meanings in the first place. The answer would be A, because 'hour' refers vaguely as time, and 'spring' in this case is not a body of water, but an action.
