What is the purpose of implementing an implicit enhancement for a purchase order transaction in...

Solution:

From the “Implementing a Customer Exit for Purchase Order” lesson on learning.sap.com, the purpose of using an implicit enhancement (via INCLUDEs in the Customer Exit) for a purchase order transaction in the SAP Business Network integration via Managed Gateway for Spend & Network is:

•D. To send accounting information in the purchase order

The lesson explains that one of the standard INCLUDEs (ARBCIG_ORDER_REQUEST_011) is used to include accounting information — such as account assignments: cost center, GL account, WBS elements, internal orders, assets — in the Purchase Order XML (OrderRequest) sent from SAP ERP/S/4HANA to the SAP Business Network. SAP Learning

The other options (filtering by company code, service map key functionality, change & cancel scenarios) are not described in that context.