体积最小的细菌是（）。

A.黏质沙雷菌

B.液化沙雷菌

C.深红沙雷菌

D.臭味沙雷菌

E.阴沟肠杆菌

Personal firewall is a technology that helps (57) intruders from accessing data on your PC via the Internet or another network, by keeping (58) data from entering or exiting your system.
Hackers do not just target national security organizations for (59) : They want your tax returns, network passwords, or bank account numbers. And you do not want the FBI kicking in your door because someone hijacked your PC to (60) in the latest denial-of-service attack on the Internet. Now that "always-on" broadband connections such as cable modems and digital subscriber line are becoming more popular, home users are at risk. Fortunately, you can protect your data. Firewalls can block (61) attacks and protect your PC from outside threats.

A. authorized B. refused C. deniedD. unauthorized