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]: Perennial grass takes ____ to five years before it is mature enough to produce adequate seed.\Question: Choose the right answer from options given a) six b) zero c) three d) no
[EX A]: c

[EX Q]: Cigarette smokers are ____ times more likely to die of lung cancer than nonsmokers.\Question: Choose the right answer from options given a) ten b) six c) four d) nine
[EX A]: a

[EX Q]: Wood chips can last about ____ years.\Question: Choose the right answer from options given a) four b) two c) seven d) nine
[EX A]:
b