楼宇访客对讲系统的多线制系统，一般线数为4+N（N为室内机数量），下面对于线数的确定
题型：单项选择题
问题：
楼宇访客对讲系统的多线制系统，一般线数为4+N（N为室内机数量），下面对于线数的确定正确的是（）。
A、通话线、开门线、电源线、接地线共用，每户再增加一条门铃线
B、门铃线、开门线、电源线、接地线共用，每户再增加一条通话线
C、门铃线、通话线、电源线、接地线共用，每户再增加一条开门线
D、门铃线、通话线、开门线、接地线共用，每户再增加一条电源线
题型：单项选择题
阅读下面的材料，判断下列句子是否符合短文内容。符合的写T，不符合的写F。
（T = True, F = False）
We can see some overhead bridges(天桥) in Yueyang city. There is one near the No.1 People's
Hospital. Another is in front of the Bus Station. As we all know, it is not safe to cross a busy road.
These bridges can help people cross the roads safely. Overhead bridges have the same use as street
crossings.
Many people think it great trouble to go through overhead bridges. The old and the young think it's
difficult for them to climb up and down the steps of the overhead bridges. But why does the government
build so many overhead bridges? That's because old people and young children walk slowly. And when
they cross a busy road using a street crossing, the traffic will be held up or maybe stopped, or even a
traffic accident may happen. With the help of the overhead bridges, people and the traffic can move at
the same time.
A lot of money has been spent building these overhead bridges. People, old or young should always
use them. This can help stop traffic accidents from happening.
( )1. There is only one overhead bridge in Yueyang city.
( )2. It is dangerous for people to cross a busy road.
( )3. All the people like using overhead bridges instead of street crossings.
( )4. Overhead bridges help people and the traffic move at the same time.
( )5. An overhead bridge can help stop a traffic accident from happening.