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: if a randomly selected positive single digit multiple of 3 is multiplied by a randomly selected prime number less than 20, what is the probability w that this product will be a multiple of 45 ?
Options: a. 1 / 32, b. 1 / 28, c. 1 / 24, d. 1 / 16, e. 1 / 14

Ex Output:
c

Ex Input:
Problem: the cost of 8 dozen pencil and 2 dozen note book is 520 rupee. if cost of 3 pencil and 4 note book is 60 rupee, then sum of the cost of 1 pencil and 1 note book will be ( in rupee.
Options: a. rs 13.51, b. rs 15.51, c. rs 16.51, d. rs 14.51, e. rs 17.51

Ex Output:
b

Ex Input:
Problem: a starts business with rs. 3500 and after 8 months, b joins with a as his partner. after a year, the profit is divided in the ratio 2: 3. what is b a ™️ s contribution in the capital ?
Options: a. 24887, b. 20778, c. 23788, d. 15750, e. 2811

Ex Output:
d