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: Reservoirs cover an area of the planet ____ times the size of Britain.\Question: Choose the right answer from options given a) two b) eight c) three d) six

A: d
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Q: Organisms have ____ forms of nucleic acid.\Question: Choose the right answer from options given a) four b) three c) two d) one

A: c
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Q: Radiant energy has ____ defining properties.\Question: Choose the right answer from options given a) seven b) zero c) two d) eight

A:
c
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