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 reduction of 25% in the price of oil enables a house wife to obtain 5kgs more for Rs.800, what is the reduced price for kg?

 Option A: 72

 Option B: 27

 Option C: 40

 Option D: 28

 Option E: 20

A: Option C
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Q: Question: A certain number of workers can do a work in 85 days. If there were 10 workers more it could be finished in 10 days less. How many workers are there?

 Option A: 75

 Option B: 30

 Option C: 28

 Option D: 24

 Option E: 32

A: Option A
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Q: Question: Out of first 30 natural numbers, one number is selected at random. The probability that it is either an even number or a prime number is ?

 Option A: 6/30

 Option B: 2/30

 Option C: 4/90

 Option D: 24/30

 Option E: 24/60

A:
Option D
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