Observe the above diagram. Spanning tree is enabled on all devices. Currently either Switch B or
C can serve as the root should Switch A fail. A client recently connected Device D, a PC running
switching application software, to Switch C port P3/3. The administrator would like to configure
Root Guard to ensure that Device D does not assume the role of root. All other parameters must
stay the same. On which interface(s) must Root Guard be enabled?

A.
P1/2

B.
P1/2, P2/2 and P3/3

C.
P1/2 and P2/2

D.
P1/1 and P1/2

E.
P2/2

F.
P3/3