Which statement about SGSN when it is serving a 2G network is true?

Which statement about SGSN when it is serving a 2G network is true?

A.
In the 2G environment, the SGSN must connect to the BSS via a “physical” circuit.

B.
Less is required of the SGSN when it is serving a 2G network.

C.
The SGSN communicates with RNC when serving a 2G network.

D.
None of the management tasks that are handled in the 3G environment by the RNC are

tasked to the SGSN in the 2G environment.