问题
单项选择题
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
答案
参考答案：A
解析：Peripherals意为“外围设备”。