单项选择题
A．someone who breaks into and uses someone else's computer B．someone who breaks commercials C．someone who fixes someone else's computer D．someone who does not know about computers
A．computers are hard to reach B．everyone has their computers locked C．computers are not very secure D．companies ask them to do it
A．it is large B．it is very small C．it takes little time for a computer to read D．it is the size of a short note