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.

Example Input: Problem: an assembly line produces 15 cogs per hour until an initial order of 60 cogs is completed. the speed of the assembly line is then immediately increased so that it can produce 60 cogs per hour until another 60 cogs are produced. what is the overall average output, in cogs per hour, for the assembly line during this whole time ?
Options: a. 20, b. 22, c. 24, d. 26, e. 28
Example Output: c

Example Input: Problem: if a man lost 10 % by selling oranges at the rate of 12 a rupee at how many a rupee must he sell them to gain 44 % ?
Options: a. 6.5, b. 7.5, c. 7, d. 8, e. 2
Example Output: b

Example Input: Problem: five women can do a work in ten days. 7 men can complete the same work in 5 days. what is the ratio between the capacity of a man and a woman ?
Options: a. 10: 7, b. 11: 10, c. 2: 3, d. 3: 2, e. none of these
Example Output:
a