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').
--------
Question: Elephants give birth to one calf every ____ to nine years on average.\Question: Choose the right answer from options given a) no b) four c) three d) seven

Answer: b


Question: Clover leaves with ____ to nine leaflets, illustrating a tendency to mutate.\Question: Choose the right answer from options given a) three b) zero c) ten d) five

Answer: a


Question: Alcoholics are nearly ____ times more likely than others to die in motor vehicle crashes.\Question: Choose the right answer from options given a) ten b) eight c) six d) five

Answer:
d