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').

Q: Most school aged children pass at least ____ stools per week, with an average of one stool per day.\Question: Choose the right answer from options given a) three b) one c) six d) zero

A: a
****
Q: Healthcare providers diagnose ____ general types of insomnia.\Question: Choose the right answer from options given a) two b) eight c) one d) three

A: a
****
Q: Gerbils usually live for ____ to four years.\Question: Choose the right answer from options given a) nine b) three c) seven d) five

A:
b
****