Which option describes how PCRF knows the amount of QoS that is needed for a Voice
over LTE call?
A.
PCRF obtains the bandwidth information over the Sy interface.
B.
PCRF obtains the bandwidth information over the Rx interface from P-CSCF.
C.
PCRF obtains bandwidth information from the TAS.
D.
PCRF has the all the bandwidth information always hard-coded in its configuration.