How should a DevOps engineer perform an AEM upgrade that preserves version history and workflows?

To perform an in-place upgrade of an AEM instance (such as upgrading from AEM 6.4 to 6.5) while preserving version history, workflow instances, and audit logs, the correct approach is an "in-place upgrade." This involves placing the new AEM quickstart JAR file in the existing installation directory, unpacking it using the -unpack command, and then starting the instance. Copying site content using Content Packages (Option C) will move the latest state of the nodes but will lose version history, ACLs (if not included), and running workflow instances.