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: Orangutans spend up to ____ hours a day eating or foraging for food.\Question: Choose the right answer from options given a) seven b) nine c) three d) six
Example Output: d

Example Input: Firebrat eggs hatch in about ____ weeks.\Question: Choose the right answer from options given a) ten b) one c) two d) no
Example Output: c

Example Input: Plant cells have ____ major parts.\Question: Choose the right answer from options given a) no b) six c) zero d) four
Example Output:
d