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?
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