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]: Amelia Island is the only territory in American history to serve under ____ flags.\Question: Choose the right answer from options given a) eight b) no c) six d) five
[EX A]: a

[EX Q]: Matter exists in ____ forms, solid, fluid and plasma.\Question: Choose the right answer from options given a) ten b) nine c) three d) five
[EX A]: c

[EX Q]: Coffee trees reach maturity between three and ____ years when their clusters of fruit turn deep red.\Question: Choose the right answer from options given a) one b) three c) nine d) four
[EX A]:
d