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: Fruit trees are usually safe after ____ years.\Question: Choose the right answer from options given a) five b) four c) no d) three

Answer: d


Question: Poles CAN occur at ____ frequency.\Question: Choose the right answer from options given a) six b) four c) zero d) eight

Answer: c


Question: Smoking is responsible for one out of ____ American deaths.\Question: Choose the right answer from options given a) five b) six c) nine d) seven

Answer:
a