Which of the following is the MOST important factor when considering environmental factors？（）
A. Server room access should be limited to authorized personnel.
B. Servers should be kept in a warm and dark environment.
C. Remove the floppy drives from the system.
D. The server administrator should ensure adequate levels of cooling.
WhichofthefollowingisMOSTcommonlypoweredusingPoE?（）
A. Routers
B. Switches
C. Laptops
D. Accesspoints
下列常用的网络连接设备论述中正确的有：（）。
A. 中继器是链路层的设备
B. 网络是链路层的设备
C. 路由器工作在网络层
D. 网关在应用层中用来连接异种网络
WhichofthefollowingprovidestheBESTsecurityandaccountabilityforaDataCenter?（）
A. Entrylogging
B. Combinationlocks
Cardkeys
Deadbolts
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