The TestKingA router is configured as shown below: TestKingA(config)# interface loopback 0 TestKingA(config-if)# ip address 192.168.16.24 255.255.255.255 As a result of this change, which of the statements below are true?（）

• A、It creates a virtual, software only, interface.
• B、It provides a way to test the convergence of OSPF routing updates.
• C、The mask of 255.255.255.255 is called a host mask.
• D、It uses a wildcard mask of 255.255.255.255.
• E、It ensures that an interface is always active for OSPF processes.
• F、Loopback interfaces must be numbered 0.