Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

[EX Q]: Problem: a company produces 50000 bottles of water everyday. if a case can hold 25 bottles of water. how many cases are required by the company to hold its one day production
Options: a. 2000, b. 4500, c. 5000, d. 8000, e. 9000
[EX A]: a

[EX Q]: Problem: after giving a discount of rs. 45 the shopkeeper gets a loss of 10 %, if the cost price is rs. 180. find the markup % ?
Options: a. 0.21, b. 0.2, c. 0.17, d. 0.21, e. 0.15
[EX A]: e

[EX Q]: Problem: 8 men, working 8 hours a day can complete a work in 18 days. how many hours a day must 12 men work to complete the same work in 12 days ?
Options: a. 6, b. 7, c. 8, d. 9, e. 10
[EX A]:
c