Solution:
From learning.sap.com, during the Fulfillment stage of the Purchase Order lifecycle, suppliers can perform these activities:
* A. Send Order Confirmations (OC) - Suppliers may send order confirmations via the SAP Business Network during the fulfillment stage. SAP Learning+1
* B. Send Advanced Ship Notices (ASN) - Suppliers can also send Advanced Ship Notices via the SAP Business Network to communicate shipping details. SAP Learning+1 The other options are not indicated in the learning materials as supplier activities during the Fulfillment stage. So the correct answe rs are: A and B.

Solution:
From learning.sap.com, during the Collaboration phase of a Collaborative Requisition, suppliers can perform the following actions (3 correct answe rs):
* C. Submit a proposal in response to a buyer's request - Suppliers are invited to submit proposals, including pricing, part numbers, item modifications, etc. SAP Learning
* D. Send a message to the buyer through the SAP Business Network - Suppliers can communicate with buyers, ask questions, negotiate details through messages during collaboration. SAP Learning+1
* E. Attach supporting documents - When submitting proposals or messages, suppliers can include attachments (supporting documents) with their responses. SAP Learning+1 The other options are not correct in this context:
* A. Cancel the collaborative requisition - Only the buyer has the option to "End Collaboration" or cancel; suppliers do not cancel the requisition. SAP Learning
* B. Finalize collaboration to trigger the purchase order - That is a buyer's action; the buyer accepts a proposal and finishes collaboration. Suppliers do not finalize the process. SAP Learning+1