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:
Onion thrips experience ____ instars.\Question: Choose the right answer from options given a) three b) six c) eight d) four

Ex Output:
d


Ex Input:
Breast cancer strikes one out of every ____ American women.\Question: Choose the right answer from options given a) one b) nine c) no d) six

Ex Output:
b


Ex Input:
Many infections have ____ symptoms and are only detected by the doctor during an annual pelvic exam.\Question: Choose the right answer from options given a) no b) two c) five d) six

Ex Output:

a