Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

[Q]: Molecules are ____ or more atoms stuck together.\Question: Choose the right answer from options given a) two b) zero c) six d) eight
[A]: a


[Q]: Some male fish return after just ____ years.\Question: Choose the right answer from options given a) no b) two c) one d) six
[A]: b


[Q]: Blue crabs feed in ____ different ways.\Question: Choose the right answer from options given a) six b) one c) three d) zero
[A]:
c