Which of the following data elements is required by SAP Ariba from a customer's existing system?

Units of Measure is a critical data element required by SAP Ariba from a customer's existing system because it defines how products and quantities are managed within the procurement process. Accurate units of measure ensure that all transactions, orders, and inventory management processes align correctly with the product specifications and the supplier's requirements.

Having proper units of measure facilitates effective communication between buyers and suppliers, helps in maintaining the integrity of the data during procurement activities, and ensures compliance with purchase agreements. Without this data, discrepancies can arise when orders are processed, leading to potential supply chain issues and misunderstandings regarding pricing, quantities, and delivery commitments.

The other options—Supplier Contact Information, Shipping Address, and Inventory Levels—are also important in the procurement process but are not universally required for the procurement functionality to operate effectively as units of measure are. Each of these other data elements may vary in necessity depending on specific business processes or transactions within different scenarios but does not have the same foundational role in facilitating procurement operations as units of measure do.