The Multilevel Navigation Menu Component in B2B Commerce supports System Link (A) and External URL (C) as types of data. System Links are used to navigate within the B2B Commerce application, facilitating a seamless user experience by linking to internal pages or resources. External URLs allow the integration of links to external websites, which can be crucial for providing additional product information, manufacturer details, or external resources. Data Source (B) and Event (D) are not typically supported by the navigation menu component as they serve different purposes in the context of B2B Commerce.