instruction:
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.
question:
Question: If x persons take y days to complete z similar jobs, how long does it take y persons to complete 1 such job?

 Option A: z

 Option B: x

 Option C: x/y

 Option D: z/x

 Option E: x/z
answer:
Option E


question:
Question: What is the units digit of 18! + 5 ?

 Option A: 2

 Option B: 3

 Option C: 4

 Option D: 5

 Option E: 6
answer:
Option D


question:
Question: What is the greatest prime factor of (11!10!) + (11!12!)?

 Option A: 11

 Option B: 17

 Option C: 19

 Option D: 23

 Option E: 29
answer:

Option C