Which statement regarding Oracle Cloud Infrastructure (OCI) Virtual Cloud Network (VCN) peering is valid?

A. A VCN peering connection is a physical network link between two VCNs within a single OCI.

B. A VCN peering connection is required for OCI Object Storage.

C. A VCN peering connection is a VPN-based connection.

D. Peered VCNs can exist in different OCI region.