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:
Calves can browse and follow their mother at three weeks old and are weaned at ____ months.\Question: Choose the right answer from options given a) five b) seven c) four d) three

Ex Output:
a


Ex Input:
Some people have ____ symptoms until the liver has been quite severely damaged.\Question: Choose the right answer from options given a) eight b) no c) nine d) ten

Ex Output:
b


Ex Input:
Network effects have ____ implications for how competition works.\Question: Choose the right answer from options given a) ten b) three c) no d) nine

Ex Output:

b