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: Pandas reach adulthood at about ____ years of age.\Question: Choose the right answer from options given a) eight b) seven c) five d) six

Answer: c


Question: Natural chlorine contains ____ isotopes.\Question: Choose the right answer from options given a) two b) six c) eight d) seven

Answer: a


Question: Most children work full-time, seven hours per day, and ____ days a week.\Question: Choose the right answer from options given a) five b) six c) no d) eight

Answer:
b