单选题 The major goal of USB was to define an external expansion bus which makes adding (70) to a PC as easy as hooking up a telephone to a wall-jack. USB 2.0 is an evolution of the USB 1.1 (71) , providing a higher performance interface.

A、 peripherals
B、 outside
C、 inside
D、 beside

【正确答案】 A

【答案解析】Peripherals意为“外围设备”。

A、 protocol
B、 specification
C、 prescript
D、 rule

【正确答案】 B

【答案解析】Specification意为“规范”，通常把USB 2.0 specification译为“USB 2.0规范(协议)”。Protocol一般在计算机中用于“网络协议”。