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 Q]: Problem: what sum of money will produce rs. 80 as simple interest in 4 years at 3 1 / 2 percent ?
Options: a. 263, b. 571.4, c. 367, d. 368, e. 339
[EX A]: b

[EX Q]: Problem: cereal a is 10 % sugar by weight, whereas healthier but less delicious cereal b is 2 % sugar by weight. to make a delicious and healthy mixture that is 3 % sugar, what should be the ratio of cereal a to cereal b, by weight ?
Options: a. 2: 9, b. 2: 7, c. 1: 7, d. 1: 4, e. 1: 3
[EX A]: c

[EX Q]: Problem: at a recent small town election for mayor a total of 963 votes were cast for the 4 candidates, the winner exceding his opponents by 53, 79 and 105 votes, respectively. how many votes were cast for each candidate ?
Options: a. 134, b. 178, c. 195, d. 166, e. 194
[EX A]:
c