Final answer:
Security is considered effective if the time to break through preventive controls by an attacker is surpassed by the organization's detection and response time. This reflects a balanced security posture that emphasizes preventive, detective, and responsive measures aligned with the security triad concept. The correct option is A. Effective.
Step-by-step explanation:
If the time an attacker takes to break through the organization's preventive controls is greater than the sum of the time required to detect the attack and the time required to respond to the attack, then security is considered effective. This scenario outlines an ideal situation where the security controls are robust enough to delay the attacker's progress until the intrusion is identified and mitigated. This suggests that the security measures in place are fulfilling their primary function of protecting organizational assets.
The effectiveness of security is often evaluated based on a concept known as the security triad, which includes prevention, detection, and response. If a security strategy successfully hampers an attacker long enough for the defensive measures (detection and response) to activate and neutralize the threat, the strategy is deemed effective. This effectiveness is a balance between preventive, detective, and responsive controls that aim to reduce the risk of successful attacks and minimize damage.
It's important not to confuse effective security with overdone or undermanaged security. Security is overdone when excessive controls are applied without adding substantial security value, and it's undermanaged when the controls are not appropriately monitored or adjusted to the evolving threat landscape. However, in this case, the security posture is appropriate, as the attacker's time to break through defenses is adequately countered by the organization's timely detection and response capabilities.