If a switch receives a superior BPDU and goes directly into a blocked state, what mechanism
must be in use?
A.
BPDU guard
B.
portfast
C.
EherCahannel guard
D.
loop guard
Explanation:
The key here is the word ‘switch’. The entire switch goes into a blocked state, meaning that it
can’t participate in STP, it is blocked. Root guard basically puts the port in a listening state
rather than forwarding, still allowing the device to participate in STP.