Refer to the exhibit. The service provider wants to ensure that switch S1 is the root switch for its own network. On which interfaces should root guard be configured to ensure that this happens?
Select the best response.

A.
interfaces 1 and 2

B.
interfaces 1, 2, 3, and 4

C.
interfaces 1, 3, 5, and 6

D.
interfaces 5 and 6

E.
interfaces 5, 6, 7, and 8

F.
interfaces 11 and 12