Cisco APICs utilize sharding to provide what function for an ACI fabric?
A. It provides scalability and reliability to the data sets generated and processed by the Distributed Policy Repository, the endpoint registry, the Observer, and the Topology Manager
B. It provides replication of application network policies across the APICs in the cluster
C. It provides a method for determining which APIC will act as the master in a fabric during the election process
D. It provides horizontal scaling ability for policy management on APICs