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]: Younger children can produce as much as ____ times more saliva than adults.\Question: Choose the right answer from options given a) one b) ten c) five d) eight
[EX A]: d

[EX Q]: Ammonia is among the ____ most abundantly produced chemicals in the world.\Question: Choose the right answer from options given a) five b) zero c) no d) eight
[EX A]: a

[EX Q]: Bipes has ____ small front limbs.\Question: Choose the right answer from options given a) two b) seven c) five d) eight
[EX A]:
a