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.

[EX Q]: Question: A and B together can do a work in 3 days. If A alone can do it in 12 days. In how many days can B alone do it?

 Option A: 4

 Option B: 6

 Option C: 8

 Option D: 10

 Option E: 25
[EX A]: Option A

[EX Q]: Question: In a school of 450 boys, 44% of Muslims, 28% Hindus, 10% Sikhs and the remaining of other communities. How many belonged to the other communities?

 Option A: 72

 Option B: 75

 Option C: 80

 Option D: 81

 Option E: 90
[EX A]: Option D

[EX Q]: Question: A can do a piece of work in 4 hours; B and C together can do it in 3 hours, which A and C together can do it in 2 hours. How long will B alone take to do it?

 Option A: 1/19

 Option B: 1/11

 Option C: 1/12

 Option D: 1/17

 Option E: 1/14
[EX A]:
Option C