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: Most people require roughly seven to ____ hours of sleep a night to stay alert through the day.\Question: Choose the right answer from options given a) eight b) ten c) one d) five

A: a
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Q: File types are ____ characters that are used to identify files.\Question: Choose the right answer from options given a) four b) zero c) ten d) one

A:
a
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