Which statement is true about the execution of the command?

Examine the RMAN command:

RMAN> BACKUP VALIDATE DATABASE;

Which statement is true about the execution of the command?

A.
Block change tracking must be enabled before executing this command.

B.
The database must be running in archivelog mode for the successful execution of this command.

C.
A complete database backup must exist before executing this command.

D.
The command checks for blocks containing all zeros, an invalid checksum, or a corrupt block header.

E.
The command checks for blocks that contain a valid checksum and matching headers and footers, but that has logically inconsistent contents.