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:
Ants have ____ distinct body parts.\Question: Choose the right answer from options given a) nine b) zero c) no d) three

Ex Output:
d


Ex Input:
Chemical interactions are essentially electron interactions of ____ atoms.\Question: Choose the right answer from options given a) six b) no c) ten d) two

Ex Output:
d


Ex Input:
Polycarbonate lenses are ____ times more impact resistant than conventional plastic or glass lenses.\Question: Choose the right answer from options given a) seven b) one c) ten d) nine

Ex Output:

c