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 aphthous ulcers heal in one to ____ weeks.\Question: Choose the right answer from options given a) two b) eight c) one d) seven

A: a
****
Q: Most children improve in three to ____ days.\Question: Choose the right answer from options given a) seven b) six c) four d) ten

A: a
****
Q: Domestic violence occurs in ____ in four families in Australia.\Question: Choose the right answer from options given a) six b) one c) nine d) no

A:
b
****