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.

Example Input: Problem: mr. loyd wants to fence his square shaped land of 120 sqft each side. if a pole is laid every 12 ft how many poles do he need ?
Options: a. 20, b. 30, c. 40, d. 50, e. 60
Example Output: c

Example Input: Problem: if the simple interest on a certain sum of money for 6 years is one – fifth of the sum, then the rate of interest per annum is
Options: a. 3.3 %, b. 7.2 %, c. 6.1 %, d. 5.0 %, e. 3.1 %
Example Output: a

Example Input: Problem: there are 38 students in a certain geometry class. if two thirds of the students are boys and 3 fourths of the boys are under 6 feet tall, how many boys in the class are under 6 feet tall ?
Options: a. 6, b. 12, c. 19, d. 24, e. 27
Example Output:
c