Final answer:
Network monitoring is not particularly effective against the insider threat due to the difficulty in differentiating between authorized and unauthorized actions. Access control, firewalls, and intrusion detection systems are more effective measures.
Step-by-step explanation:
The control that is not particularly effective against the insider threat is b) Network monitoring.
Network monitoring is primarily used to identify and analyze network traffic, looking for suspicious or unauthorized activity. However, it may not be as effective in detecting insider threats because the activity of insiders is often within the normal range of the network traffic. Additionally, insiders may have legitimate access to the network, making it difficult to differentiate between their authorized and unauthorized actions.
On the other hand, access control, firewalls, and intrusion detection systems are all effective measures against the insider threat. Access control ensures that only authorized individuals can access sensitive information and systems. Firewalls prevent unauthorized access to a network by monitoring and controlling incoming and outgoing traffic. Intrusion detection systems detect and respond to any suspicious or malicious activities on a network.