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').

Input: Consider Input: Mothers usually give birth to one, two, or ____ babies at a time.\Question: Choose the right answer from options given a) three b) zero c) five d) ten

Output: a

Input: Consider Input: Reverse osmosis uses three to ____ gallons of water to produce one gallon of drinking water.\Question: Choose the right answer from options given a) six b) eight c) five d) ten

Output: d

Input: Consider Input: Women are almost ____ times as likely to be in nursing homes as men.\Question: Choose the right answer from options given a) three b) no c) eight d) one
Output: a