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: On dividing 21 by a number, the quotient is 10 and the remainder is 1. Find the divisor.

 Option A: 1

 Option B: 2

 Option C: 4

 Option D: 6

 Option E: 7
[A]: Option B


[Q]: Question: P alone can complete a piece of work in 14 days. Work done by Q alone in one day is equal to one-third of the work done by P alone in one day. In how many days can the work be completed if P and Q work together?

 Option A: 6 (1/4

 Option B: 21/2 days

 Option C: 7 (3/4

 Option D: 8/5 days

 Option E: 9 (3/4
[A]: Option B


[Q]: Question: Four staff members at a certain company worked on a project. The amounts of time that the four staff members worked on the project were in the ratio 2 to 3 to 5 to 6. If one of the four staff members worked on the project for 60 hours, which of the following CANNOT be the total number of hours that the four staff members worked on the project?

 Option A: 480

 Option B: 160

 Option C: 320

 Option D: 192

 Option E: 240
[A]:
Option E