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.

[Q]: Problem: in a certain pond, 50 fish were caught, tagged, and returned to the pond. a few days later, 50 fish were caught again, of which 5 were found to have been tagged. if the percent of tagged fish in the second catch approximates the percent of tagged fish in the pond, what is the approximate number of fish in the pond ?
Options: a. 400, b. 500, c. 1,250, d. 2,500, e. 10,000
[A]: b


[Q]: Problem: a sells a bicycle to b and makes a profit of 50 %. b sells the same bicycle to c at a profit of 25 %. if the final s. p. of the bicycle was rs. 225, find out the cost price of the bicycle for a.
Options: a. 237, b. 126, c. 971, d. 611, e. 120
[A]: e


[Q]: Problem: on a map the distance between two mountains is 312 inches. the actual distance between the mountains is 136 km. ram is camped at a location that on the map is 34 inch from the base of the mountain. how many km is he from the base of the mountain ?
Options: ['a. 14.83', 'b. 14.81', 'c. 14.8', 'd. 14.82', 'e. 14.12']
[A]:
d