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: Electrons have almost ____ mass and are negatively charged.\Question: Choose the right answer from options given a) three b) seven c) zero d) no

A: d
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Q: Double price is based on two golfers sharing ____ room.\Question: Choose the right answer from options given a) one b) zero c) six d) nine

A: a
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Q: Birds are the only living organisms with feathers, and ____ dinosaurs have been found with feathers.\Question: Choose the right answer from options given a) ten b) eight c) no d) four

A:
c
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