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 Input:
Problem: three 6 faced dice are thrown together. the probability that exactly two dice show the same number on them is
Options: a. 5 / 15, b. 5 / 12, c. 5 / 19, d. 5 / 12, e. 5 / 11

Ex Output:
b

Ex Input:
Problem: a bag of potatoes weighs 60 lbs divided by half of its weight. how much does the bag of potatoes weight ?
Options: a. 20 lb, b. 11 lb, c. 10 lb, d. 15 lb, e. 5 lb

Ex Output:
b

Ex Input:
Problem: a company recently conducted a survey and found that 20,000 of its customers live in rural areas. if the number of customers who live in urban areas is 100 percent greater than the number of customers who live in rural areas, how many customers live in urban areas ?
Options: a. 40,000, b. 45,000, c. 50,000, d. 55,000, e. 60,000

Ex Output:
a