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').

[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
[A]: a


[Q]: Female bilbies have a backward-opening pouch with ____ nipples.\Question: Choose the right answer from options given a) no b) two c) five d) eight
[A]: d


[Q]: Fawns are weaned when three to four months old, and are sexually mature at about ____ months.\Question: Choose the right answer from options given a) seven b) six c) four d) five
[A]:
b