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.

Input: Consider Input: Problem: for each color copy, print shop x charges $ 1.20 and print shop y charges $ 1.70. how much greater is the charge for 40 color copies at print shop y than at print shop x ?
Options: a. $ 14, b. $ 16, c. $ 18, d. $ 20, e. $ 22

Output: d


Input: Consider Input: Problem: a rhombus has area 432 sq m, one diagonal is 36 cm. find other diagonal ?
Options: ['a. 2400 m', 'b. 2500 m', 'c. 2600 m', 'd. 2700 m', 'e. 2900 m']

Output: a


Input: Consider Input: Problem: a square with sides of 15 units each. what would be the area of the square. consider a square as a combination of two right angled triangles.
Options: ['a. 100', 'b. 256', 'c. 225', 'd. 81', 'e. 144']


Output: c