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: Serial transfer is the sequential transmission of the ____ bit-voltages that constitute a byte.\Question: Choose the right answer from options given a) ten b) eight c) two d) four

A: b
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Q: Most internal parasites are specific to one or ____ species.\Question: Choose the right answer from options given a) seven b) three c) two d) five

A: c
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Q: Significant power is observed in the magnetic field oscillations with periods of ____ minutes.\Question: Choose the right answer from options given a) three b) one c) seven d) five

A:
d
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