In SAP Event Mesh, topic subscriptions follow a defined hierarchical string structure:

Namespace → Defines the domain or context (e.g., sap/s4/beh/businesspartner).

Topic name → Specifies the exact event (e.g., BusinessPartner/Changed).

Separators (/) → Used to concatenate namespace and event details into a full subscription string.

Other options:

API key, Client ID, and Authentication token → Used for connectivity but not part of the topic string.

Business Partner ID, Change type, Event timestamp → Payload details, not part of the subscription string.

Source/Target system → Not required for constructing the topic name.

Thus, the correct components are Namespace, Topic name, Separator.