What identifies the authority for the classification of information?

The classification authority block is the correct choice because it specifically indicates who has the authority to classify the information, along with the relevant classification guidance. This block typically contains the name of the individual or the department that classified the information, as well as the date of the classification. It serves as a pivotal reference point that establishes the legitimacy and responsibility behind the classification, ensuring that there is accountability and traceability for the classified status of the information.

The other options do not serve the same purpose. The classification title indicates the sensitivity level of the information but does not specify who has the authority to classify it. The type of information refers to the category of content being classified but lacks the designation of classified authority. The declassification date is important for information lifecycle management but does not convey the authority responsible for the classification decision itself.