Which of the following best describes a data breach?

A data breach is best defined as an unauthorized access or retrieval of sensitive information. This definition captures the essence of what constitutes a data breach: when individuals or entities gain access to confidential data—such as personal, financial, or proprietary information—without permission.

Data breaches typically involve malicious intent and can lead to significant consequences, such as identity theft, financial loss, and damage to an organization’s reputation. It emphasizes the criticality of safeguarding information and implementing robust security measures to prevent such unauthorized access.

In contrast, the other options do not adequately encompass the concept of a data breach. While the loss of business revenue due to cyber threats can be a consequence of a data breach, it does not directly define what a data breach is. A security policy violation without serious consequences may indicate reckless behavior, but it doesn't necessarily involve unauthorized access to sensitive data. Lastly, a routine maintenance error in data administration relates to operational issues rather than the illegal or unauthorized act of accessing information, which is central to understanding a data breach.