Which of the following strategies helps maintain data confidentiality by preventing unauthorized access?

The correct choice involves a strategy specifically designed to maintain data confidentiality by establishing control over who can access certain types of data. Classification-based data blocking involves categorizing data based on its sensitivity and applying different levels of access control accordingly. By classifying data as confidential, internal, or public, organizations can put in place rules that restrict access to that information to only those individuals or systems that have the appropriate permissions. This prevents unauthorized access, helping to ensure that sensitive information is only seen or handled by those who are properly authorized to do so. The classification helps inform protective measures, including encryption, access controls, and monitoring practices, all of which are essential for maintaining the confidentiality of sensitive information.