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: Many scientists believe the neutrino has ____ mass at all.\Question: Choose the right answer from options given a) eight b) zero c) two d) no

A: d
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Q: Embrasures have ____ functions.\Question: Choose the right answer from options given a) three b) seven c) zero d) nine

A: a
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Q: Lightning is ____ times hotter than the surface of the sun.\Question: Choose the right answer from options given a) zero b) five c) three d) two

A:
c
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