What are two functions of a Network Services Orchestrator in an NFV environment? (Choose two.)

NSOs function at the resource-facing services layer to provide comprehensive lifecycle management for network services, including instantiation, scaling, and termination of resources and services in an NFV environment.

NSOs offer an API-based northbound interface to allow integration with external systems, such as Operation Support Systems (OSS) and Business Support Systems (BSS), enabling automated service provisioning and management.

While NSOs interact southbound with network elements, they do so often using specific protocols like NETCONF/YANG, and this description is less precise than the northbound API for integration with 'systems'.

NSOs provide northbound interfaces to higher-level systems via APIs, which are typically application-specific or standard REST/SOAP, not necessarily 'standards-based' in the same context as southbound protocols like NETCONF.

NSOs operate at the service and resource orchestration layers, not directly at the customer-facing services layer, which is typically handled by BSS/OSS systems for customer interaction.