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: the total marks obtained by a student in mathematics and physics is 50 and his score in chemistry is 20 marks more than that in physics. find the average marks scored in mathamatics and chemistry together.
Options: a. 15, b. 25, c. 35, d. 45, e. 55

Ex Output:
c


Ex 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

Ex Output:
b


Ex Input:
Problem: the perimeter of a square is equal to the perimeter of a rectangle of length 17 cm and breadth 14 cm. find the circumference of a semicircle whose diameter is equal to the side of the square. ( round off your answer to two decimal places )
Options: a. 23.57, b. 23.54, c. 23.5, d. 24.35, e. 24.51

Ex Output:

d