You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.

In a certain game, different colored tokens are worth different numbers of points. A blue token and a red token together are worth a total of 12 points, a blue token and a green token together are worth a total of 13 points, and a red token and a green token together are worth a total of 15 points. How many points is a blue token worth?
(A)5 points (B)6 points (C)7 points (D)8 points (E)9 points
A