Which two statements about Cisco SGSN are true? (Choose two.)
A. Cisco SGSN can support 2G or 4G Cisco SGSN instances on a single Cisco ASR 5000 system
B. Cisco SGSN adheres to defined 3GPP standards for mobility management, packet data, and accounting
C. Cisco SGSN supports paging, authentication, and P-TMSI reallocation
D. Cisco SGSN supports single Cisco SGSN and GGSN instances on multiple Cisco ASR 5000 requests
