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:
Water is present in all ____ phases in Earth s atmosphere.\Question: Choose the right answer from options given a) six b) nine c) two d) three

Ex Output:
d


Ex Input:
All spider mites have ____ legs and a lack of a separate head.\Question: Choose the right answer from options given a) eight b) four c) ten d) one

Ex Output:
a


Ex Input:
Skin is classified into ____ groups according to the tendency to sunburn.\Question: Choose the right answer from options given a) one b) three c) eight d) six

Ex Output:

d