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]: Voles are prolific breeders and can produce four to ____ litters a year.\Question: Choose the right answer from options given a) four b) two c) six d) three
[EX A]: c

[EX Q]: Control is defined as a dead plant with ____ signs of life.\Question: Choose the right answer from options given a) ten b) nine c) no d) zero
[EX A]: c

[EX Q]: Otters have ____ to three pups in late spring.\Question: Choose the right answer from options given a) two b) nine c) five d) one
[EX A]:
a