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: during a given week a programmer spends 1 / 4 of his time preparing flow chart, 3 / 8 of his time coding and the rest of the time in debugging the programs. if he works 48 hours during the week, how many hours did he spend debugging the program.
Options: a. 15 hrs, b. 16 hrs, c. 18 hrs, d. 19 hrs, e. 17 hrs
Example Output: c

Example Input: Problem: a waitress ' s income consists of her salary and tips. during one week, her tips were 3 / 4 of her salary. what fraction of her income for the week came from tips ?
Options: a. 1 / 9, b. 1 / 6, c. 3 / 7, d. 4 / 9, e. 5 / 9
Example Output: c

Example Input: Problem: the price of an item is discounted 5 percent on day 1 of a sale. on day 2, the item is discounted another 10 percent, and on day 3, it is discounted an additional 15 percent. the price of the item on day 3 is what percentage of the sale price on day 1 ?
Options: a. 28 %, b. 40 %, c. 64.8 %, d. 76.5 %, e. 78 %
Example Output:
d