In SAP Project System (PS), planned revenue for a WBS element can be established early in the sales cycle by transferring values from a sales quotation. This allows for preliminary financial planning before a firm customer commitment. Actual revenue is realized later in the process. When a billing document (invoice) is created with reference to a sales order that is account-assigned to a WBS element, the system posts the revenue amount as an actual value to that WBS element upon release to financial accounting. This is the standard, integrated process for recognizing actual project revenue.

A. Planned revenue does not strictly require a sales order; it can also be planned manually (e.g., using transaction CJ42) or transferred from a quotation.

C. A billing plan within a sales order determines the billing schedule and amounts, but it does not post revenue. The billing document is the object that triggers the actual posting.

1. SAP S/4HANA Help Portal, "Revenue Planning": This official documentation states, "You can plan revenues as follows: ... By transferring data from SD documents (inquiry, quotation, sales order)". This confirms that planned revenue can be transferred from a quotation (Answer B) and that a sales order is not the only source, making the term "requires" in Answer A incorrect.

2. SAP S/4HANA Help Portal, "Actual Revenue": The documentation specifies, "The system posts actual revenues to the project when you create billing documents for the project." It further details that this occurs through Sales and Distribution (SD) billing, where the sales order item is assigned to a WBS element. This directly supports that the billing document posts the actual revenue (Answer D) and clarifies that the billing plan is for scheduling, not posting (making Answer C incorrect).

3. SAP S/4HANA Product Assistance, "Project-Related Sales and Distribution": This section outlines the end-to-end process, confirming that "When you create the billing document for the sales order item, the revenue is posted to the WBS element specified in the sales order item." This reinforces the correctness of Answer D.