Instructions: 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: Problem: the average of runs of a cricket player of 10 innings was 33. how many runs must he make in his next innings so as to increase his average of runs by 4 ?
Options: a. 77, b. 79, c. 85, d. 87, e. 89
Output:
a