In SRVCC, what is the role of STN-SR?

In SRVCC, what is the role of STN-SR?
A . Used for SCCAS subsequent addressing ATCF
B . used for filling the SIP MESSAGE which sent by the SCCAS to ATCF
C . indicates the access domain where the P-CSCF/ATCF is located.
D . Used for SRVCCIWF subsequent addressing ATCF

View Answer

Answer: A