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: Cleavage is perfect in ____ directions, prismatic.\Question: Choose the right answer from options given a) two b) nine c) three d) seven
Example Output: a

Example Input: Acoustic guitars come in ____ types.\Question: Choose the right answer from options given a) two b) ten c) one d) four
Example Output: a

Example Input: Many ticks can live as long as three to ____ months between each stage.\Question: Choose the right answer from options given a) five b) four c) seven d) ten
Example Output:
a