A content token links app licenses to MDM for distribution. The Apple Business Manager User Guide states, "To configure Managed Distribution, download the content token from Apple Business Manager and upload it to your MDM server. This token authorizes the MDM to manage and distribute apps to enrolled devices." Options B, C, and D are unrelated to app distribution.
Reference:
Apple Business Manager User Guide, "Apps and Books" section.
Mobile Device Management Protocol Reference, "App Management" section.