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').

Example Input: Wind is renewable, and produces ____ emissions or by-products.\Question: Choose the right answer from options given a) five b) nine c) zero d) no
Example Output: d

Example Input: Most internal parasites are specific to one or ____ species.\Question: Choose the right answer from options given a) seven b) three c) two d) five
Example Output: c

Example Input: Takins can even balance on their hind hooves to nibble on vegetation ____ feet above ground.\Question: Choose the right answer from options given a) two b) no c) nine d) eight
Example Output:
d