shouldn't play computer games too-----.A.many B.much C.more

选B.too much用作副词,修饰动词play.
too many+可数名词的复数形式.
too much常用作副词或代词,也可以用作形容词修饰不可数名词.如：
Is watching TV too much good or bad for your health?电视看得太多对你的健康有益还是有害?
You've given me too much.你给我的太多了.
We've had too much rain lately.最近我们这里的雨下得太多了.
too many常用作形容词,修饰可数名词复数.如：
They built too many buildings last year.去年他们建了许多楼房.