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:
Hummingbirds feed every ____ to fifteen minutes from sun-up to sundown.\Question: Choose the right answer from options given a) nine b) seven c) four d) ten

Ex Output:
d


Ex Input:
Collars come in ____ shapes.\Question: Choose the right answer from options given a) six b) two c) four d) zero

Ex Output:
b


Ex Input:
Shamans live in ____ worlds at the same time.\Question: Choose the right answer from options given a) three b) two c) eight d) no

Ex Output:

b