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: 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

Example Input: Tilt consists of ____ small surface vents.\Question: Choose the right answer from options given a) zero b) three c) seven d) no
Example Output: b

Example Input: Black people are at ____ times more risk than white people.\Question: Choose the right answer from options given a) five b) four c) nine d) three
Example Output:
b