What are the three classes of crisis maintenance?

The correct choice, which identifies the three classes of crisis maintenance, is Class A, Class B, and Class C. This classification is often used in the context of emergency and crisis management to categorize the types of maintenance practices that should be employed in response to varying levels of urgency and complexity during a crisis.

Class A generally pertains to urgent and high-priority situations requiring immediate attention to restore or maintain operations. Class B may involve situations that are important but not critical, often allowing for slightly longer response times, whereas Class C can cover lower-priority issues that have less immediate impact and can be addressed as resources allow. Understanding these classifications helps responders prioritize tasks effectively, ensuring that the most critical elements of crisis maintenance are handled promptly.

In contrast, other options provided refer to different concepts. Class 1, Class 2, and Class 3 typically align with classifications unique to other systems or methodologies not directly representing crisis maintenance. Terms like "Complete, Immediate, Delayed" and "Emergency, Routine, Preventive" also represent frameworks that incorporate maintenance strategies but do not specifically define the three classes of crisis maintenance as outlined in the question.