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: A and B complete a job in 6 days. A alone can do the job in 15 days. If B works alone, how many days will it take to complete the job?

 Option A: 8

 Option B: 10

 Option C: 12

 Option D: 14

 Option E: 16
[A]: Option B


[Q]: Question: If 0 < x < 1 and x ≠ 0, which of the following inequalities must be true?
I. x^3 < x
II. x^2 < |x|
III. x^4 – x^5 > x^3 – x^2

 Option A:  I only

 Option B:  II only

 Option C:  III only

 Option D:  II and III only

 Option E:  I, II, and III
[A]: Option B


[Q]: Question: In a certain group of 10 members, 4 members teach only French and the rest teach only Spanish or German. If the group is to choose 4-member committee, which must have at least 1 member who teaches French, how many different committee can be chosen ?

 Option A: 174

 Option B: 171

 Option C: 186

 Option D: 196

 Option E: 200
[A]:
Option B