What marking indicates that information is exempt from automatic declassification?

The marking that indicates information is exempt from automatic declassification is the phrase "Exempt from Declassification Under Executive Order 13526." This marking signifies that certain categories of information are not subject to declassification after the designated time period has expired. This provision is important for protecting sensitive information that, if released, could harm national security or reveal important intelligence sources and methods. Under Executive Order 13526, specific reasons for exemption include ongoing military operations, information related to the protection of intelligence sources, or information crucial to national security.

The other options do not clearly identify such exemptions. For instance, "Classified Under Executive Order 13526" denotes that the information is classified but does not specify any declassification exemptions. Similarly, the "Confidential Information Mark" simply classifies the content without addressing declassification. "Restricted Data Marking" specifically refers to nuclear-related information but does not indicate broader exemption criteria under the Executive Order. Therefore, the selected marking is the most accurate representation of the exemption status concerning automatic declassification.