You're an Org Admin for an airline's Slack Enterprise Grid.

According to Slack Enterprise Grid documentation:

"To allow users to integrate external tools into workflows, admins must enable steps from apps and allow workflows to include webhook triggers."

Also,

"Enabling Workflow Builder and allowing users to create workflows (except Guests) ensures flexibility."

While A (App Managers) grants permission to approve apps, it is not needed for creating workflows. Channel emails (C) are unrelated. Workflow creation policy (E) is important too but the critical steps for app usage and webhook integration are B and D.

(Reference: Slack Administration Study Guide - Workflow Builder with External Integrations)

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