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.

Problem: how many quarters are equal to 7 dollars ?
Options: a. 1, b. 28, c. 12, d. 9, e. 7
b

Problem: if each participant of a chess tournament plays exactly one game with each of the remaining participants, then 276 games will be played during the tournament. find the number of participants.
Options: a. 20, b. 22, c. 24, d. 26, e. 28
c

Problem: how many shots of 1 cm radius can be prepared from a sphere of 5 cm radius ?
Options: a. 33, b. 88, c. 27, d. 125, e. 199

d