It has become necessary to configure an existing serial interface to accept a second Frame Relay virtual circuit.Which of the following processes are required to accomplish this task?（）
- A configure static frame relay map entries for each subinterface network.
- B remove the ip address from the physical interface
- C create the virtual interfaces with the interface command
- D configure each subinterface with its own IP address
- E disable split horizon to prevent routing loops between the subinterface networks
- F encapsulate the physical interface with multipoint PPP