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]: Harbor porpoises live in groups averaging one to ____ individuals and are very skittish.\Question: Choose the right answer from options given a) seven b) five c) two d) three
[EX A]: d

[EX Q]: Water weighs about ____ pounds per gallon.\Question: Choose the right answer from options given a) seven b) ten c) zero d) nine
[EX A]: b

[EX Q]: Healthy children get at least ____ colds a year.\Question: Choose the right answer from options given a) six b) one c) two d) nine
[EX A]:
a