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:
Corms are undifferentiated, uniform, and contain ____ rings when cut apart.\Question: Choose the right answer from options given a) no b) three c) one d) zero

Ex Output:
a


Ex Input:
China has about ____ in four of all smokers in the world.\Question: Choose the right answer from options given a) one b) seven c) ten d) six

Ex Output:
a


Ex Input:
Adelgids can kill a fir tree in as little as ____ years.\Question: Choose the right answer from options given a) two b) three c) eight d) nine

Ex Output:

b