Log data should be protected ____________.

Protecting log data at a lower sensitivity level than the source systems would make it a weaker link, allowing attackers to potentially access or tamper with logs more easily, undermining security monitoring and incident response.

Log data often contains sensitive information about system activities, security events, and user actions, which can be as sensitive as, or even more sensitive than, the data on the systems themselves. Protecting it at least at the same sensitivity level ensures that adversaries cannot easily compromise the logs to hide their tracks or gain insights into system weaknesses.

While encryption in transit, at rest, and in use is an important method of protection, it describes a technical control rather than the sensitivity level requirement for protection, and it might not be universally required for all log data across all sensitivity levels.

'According to NIST guidelines' is too general; while NIST provides excellent guidance, the most specific and accurate principle among the choices for log data protection sensitivity is comparing it to the source system's sensitivity.