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 Input:
Lions have ____ distinct vocalizations including roars, grunts and growls.\Question: Choose the right answer from options given a) eight b) six c) four d) nine

Ex Output:
d


Ex Input:
Sound waves travel through the air in a similar manner, but in all ____ dimensions.\Question: Choose the right answer from options given a) three b) five c) nine d) one

Ex Output:
a


Ex Input:
Puppy teeth begin to shed and be replaced by permanent adult teeth at about ____ months of age.\Question: Choose the right answer from options given a) eight b) ten c) five d) four

Ex Output:

d