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: Japan is a highly urbanised country, with approximately three in every ____ people living in cities.\Question: Choose the right answer from options given a) seven b) two c) four d) eight

A: c
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Q: All cattle have a ____ chambered stomach, consisting of a rumen, reticulum, omasum and abomasum.\Question: Choose the right answer from options given a) ten b) four c) six d) two

A: b
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Q: Stars are classified into ____ main luminosity classes.\Question: Choose the right answer from options given a) eight b) five c) three d) four

A:
b
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