Sam, a cleared DoD employee, receives an e-mail message on his NIPRNET account that contains classified information. Who should he notify first of this incident?

Security Manager

Explanation:

In such a scenario, the first individual that should be notified of this e-mail would be the Security Manager. This is mainly because the security manager's main responsibility is dealing with high-level IT security issues and supervising employees who implement and configure security measures. The suspicious e-mail could be a virus or a breach in security which is the Security Manager's duty to analyze the e-mail and decide how to handle the situation.

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