【阅读判断】One problem with this design is that the mouse gets dirty as the ball rolls over the surface and picks up dirt. Eventually you have to clean your mouse.
Q: When an ordinary computer mouse gets dirty, it has to be replaced with a new one.
A、True
B、False
C、Not Given
【正确答案】：B
【题目解析】：答案选B。题中说鼠标脏了，就得换用新的。这一说法与原文不符。原文说的是鼠标脏了，可以擦干净再用。it has to be replaced with a new one 与 you have to clean your mouse 不符。所以选B。
