What is an essential feature of maintaining network security in law enforcement agencies?

An essential feature of maintaining network security in law enforcement agencies is the implementation of virus protection. This is vital because law enforcement agencies handle sensitive and confidential information, and the presence of viruses can lead to unauthorized access and data breaches. Viruses and malware can compromise system integrity, allowing malicious actors to manipulate or steal critical data. Implementing robust virus protection measures ensures that these threats are detected and neutralized before they can cause harm to the network and its resources.

While other options like cost-effective monitoring, regular software updates, and restricted user access contribute significantly to network security, the specific necessity for virus protection addresses the immediate and ongoing threat posed by harmful software programs that can infiltrate agency networks.