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 each of 4 digit code is formed of integers from 1 to 50, inclusively, and each of the digits are different, how many possible codes are there?

 Option A: 5527200

 Option B: 5586300

 Option C: 5598600

 Option D: 5547800

 Option E: 2569800

A: Option A
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Q: Question: total 36 matches are conducted in Knockout match type. How many players will be participated in that tournament?

 Option A: 35

 Option B: 36

 Option C: 21

 Option D: 32

 Option E: 26

A:
Option A
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