You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: If x, y, and z are positive integers such that x is a factor of y and y is a factor of z, which of the following is NOT necessarily an integer?

Option A: (x + y

Option B: (y + z

Option C: yz/x

Option D: (2y + 3z

Option E: (xy + z

A: Option A
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Q: Question: If x is an integer such that 5 < x < 21, 7 < x < 18, 13 > x > 2, 12 > x > 9, and x + 1 < 13, then x is

Option A: 3

Option B: 5

Option C: 7

Option D: 9

Option E: 11

A: Option E
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Q: Question: The average age of a husband and a wife is 25 years when they were married five years ago but now the average age of the husband, wife and child is 21 years(the child was born during the interval). What is the present age of the child?

Option A: 3 years

Option B: 5 years

Option C: 9 years

Option D: 4 years

Option E: 1 years

A:
Option A
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