The correct answer is C — Impact.

According to WGU Cybersecurity Architecture and Engineering (KFO1 / D488) materials, when evaluating the severity of an incident, the immediate and potential impact on operations, patient care, finances, or reputation is the most critical factor. In this scenario, the interruption to patientcare due to encrypted records signifies a major operational impact, making it the most important consideration.

Threat actors (A) identify who is behind the attack, not the severity. Risk (B) encompasses impact and likelihood but is broader. Likelihood (D) concerns the probability of an event happening, not its current severity.

Reference Extract from Study Guide:

"Impact refers to the actual or potential harm that results from a security incident, including effects on operations, financial loss, or harm to individuals."

— WGU Cybersecurity Architecture and Engineering (KFO1 / D488), Incident Response and Management

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