Which is a preemptive measure taken to reduce the risk of an attack?

The selection of risk avoidance techniques as a preemptive measure reflects a proactive approach to risk management. In the context of security and defense, these techniques are designed to eliminate vulnerabilities and threats before they can be exploited.

Risk avoidance might involve changing plans to sidestep potential risks, implementing more secure systems, or adopting strategies that reduce exposure to threats. For instance, if a particular operation is deemed too risky due to identified threats, opting not to engage in that operation altogether is a straightforward application of risk avoidance.

This approach contrasts with the other options, which focus on responses to incidents after they occur or require training personnel to respond effectively to attacks that may happen. While response planning and incident response training are critical components of a comprehensive security strategy, they are reactive rather than preemptive. Post-incident analysis also falls into the category of responding to attacks by examining what went wrong and how to improve future responses. Thus, employing risk avoidance techniques stands out as a definitive method for precluding potential threats before they manifest.