Which redundancy measure is considered appropriate for critical systems?

Employing a backup power generator is a critical redundancy measure for systems that require high availability and reliability. This approach ensures that critical systems remain operational during power outages or fluctuations. By having a backup power source, organizations can maintain continuous service, preventing downtime that could lead to significant losses in productivity, revenue, or trust from customers.

Although options like using multiple internet connections can provide improved connectivity and reliability, they do not address power failure specifically. Regularly updating software is essential for security and performance but does not directly relate to maintaining operation during power disruptions. Similarly, implementing password policies is important for security but does not contribute to the redundancy of power supply necessary for critical systems. Therefore, a backup power generator stands out as the best choice for ensuring operational continuity in the face of potential power issues.