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.
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Question: Question: For an employee to qualify for early retirement at a certain company, the sum of the employee's age and years of service must be at least 72, If Sue was K years old when she was hired by the company, what is the minimum age at which she could possibly qualify for early retirement.

Option A: K+36

Option B: 2K+36

Option C: (72+K

Option D: (72-K

Option E: 2(72-K

Answer: Option C

Question: Question: A code is to be made by arranging 9 letters. five of the letters used will be the letter A, two of the letters used will be the letter B, one of the letters used will be the letter C, and one of the letters used will be the letter D. If there is only one way to present each letter, how many different codes are possible?

Option A: 42

Option B: 210

Option C: 46820

Option D: 84002

Option E: 90720

Answer: Option E

Question: Question: A does a work in 20days and B does the same work in 5days. In how many days they together will do the same work?

Option A: 1

Option B: 2

Option C: 3

Option D: 4

Option E: 5

Answer:
Option D