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').

[EX 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
[EX A]: c

[EX Q]: Molecules are ____ or more atoms stuck together.\Question: Choose the right answer from options given a) two b) zero c) six d) eight
[EX A]: a

[EX Q]: Chinese music has a ____ thousand year history.\Question: Choose the right answer from options given a) two b) zero c) three d) no
[EX A]:
c