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:
Western culture offers only ____ genders, man or woman.\Question: Choose the right answer from options given a) three b) two c) one d) four

Ex Output:
b


Ex Input:
Alleles segregate independently yielding ____ possible allelic combinations in gametes.\Question: Choose the right answer from options given a) ten b) one c) four d) nine

Ex Output:
c


Ex Input:
Most people require six to ____ hours of sleep.\Question: Choose the right answer from options given a) no b) six c) eight d) nine

Ex Output:

c