Which form of services is responsible for defining and consuming semantically rich data models?

The correct answer is Core Data Services. These services play a crucial role in the SAP HANA environment by allowing developers to define and consume semantically rich data models. Core Data Services (CDS) use a declarative syntax for defining entity types and associations, enabling developers to create complex data models that can capture business semantics. This capability is particularly important for creating meaningful views that can easily be consumed by applications and tools.

Core Data Services also support various features, such as annotations and association definitions, facilitating a rich data modeling experience. These services ensure that the data is not only stored efficiently but also represented in a manner that captures its business context.

In contrast, the other options either refer to services that do not focus specifically on semantic data modeling or do not exist within the HANA framework in the same way that CDS does. Thus, Core Data Services clearly stand out as the responsible entity for defining and consuming semantically rich data models within SAP HANA.