The correct answers are C, D, and E . Grid migration preparation requires identity cleanup and collaboration-boundary planning before the workspace is moved into Enterprise Grid. Addressing duplicate usernames helps reduce ambiguity and improves post-migration clarity for users and admins. Ensuring user emails match SSO is more critical because user identity matching depends heavily on email alignment between Slack and the identity provider; mismatches can produce duplicate accounts or login problems. Disconnecting Slack Connect channels is also part of migration preparation when external channel relationships cannot simply be carried forward unchanged or require re-establishment under the Enterprise Grid governance model. Option A, accepting the migration invitation, occurs as part of the migration execution flow, but it is not one of the core preparation cleanup actions being tested. Option B is wrong because guests do not need to be removed wholesale; guest strategy should be reviewed and handled deliberately. Option F is also wrong because apps should be reviewed and governed, not automatically removed from all migrating workspaces.

Reference topic: Delivery and Migration — grid migration readiness, identity cleanup, SSO alignment, duplicate user prevention, and Slack Connect migration preparation.

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