What is Core Data Services (CDS)?

A、 A collection of services that provide information about the data volumes of the SAPHANA core tables
B、 A collection of services for ABAP application programming that provide access to theCore features of the SAP HANA database management system
C、 A collection of core features and services that provide data from the ABAP applicationServer layer to the user interface
D、 A collection of domain-specific languages and services for definition and consumption ofSemantically rich data models