Which of the following statements is correct?

In a certain network, it is planned to use an S3610 switch as a RADIUS client and two IMC servers as RADIUS servers to complete user security authentication access.

Which of the following statements is correct?
A . When configuring the S3610, the RADIUS server type that should be selected should be Extend.
B . If the two IMC servers can adopt the master-slave mode, then the two RADIUS server IP addresses configured on the S3610 must be the same
C . Two IMC servers cannot work in master-slave mode
D . By default, the IP address of the RADIUS server on the S3610 is 192.168.1.1

Answer: A