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: 23, 18, 16, 11, 9, 4 ?

 Option A: 3

 Option B: 2

 Option C: 7

 Option D: 5

 Option E: 1

A: Option B
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Q: Question: Which of the following CANNOT be weighed using a balance scale and these unit weights: 1, 4, 7, and 10

 Option A: 13

 Option B: 15

 Option C: 17

 Option D: 19

 Option E: 21

A: Option A
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Q: Question: Calculate the L.C.M of 7/10, 8/ 9, 3/8, 5/12 is :

 Option A: 840

 Option B: 70

 Option C: 740

 Option D: 140

 Option E: 940

A:
Option A
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