A data center has had a power outage. Which of the following should the administrator do FIRST once the power is restored?

In a post-outage scenario, the immediate priority is to restore core business operations. Identifying and bringing up the most critical systems first ensures that essential services are quickly resumed, minimizing business impact and allowing the organization to operate with fundamental functionalities, adhering to disaster recovery priorities.

Retrieving backup tapes is necessary if data corruption or system failure occurred, but it is not the first step if power is simply restored and systems need to be brought back online.

Powering on the least critical systems first is counterproductive to business continuity, as it delays the restoration of essential services that directly support core operations.

Determining the cause of the outage and installing UPS systems are crucial for long-term prevention but are not the immediate priority for an administrator whose primary task is to restore services once power is already back.