Which three statements about bridge assurance are true? (Choose three.)
A.
Bridge assurance must be enabled on both ends of a link.
B.
Bridge assurance can be enabled on one end of a link or on both ends.
C.
Bridge assurance is enabled on STP point-to-point links only.
D.
Bridge assurance is enabled on STP multipoint links only.
E.
If a bridge assurance port fails to receive a BPDU after a timeout, the port is put into a blocking
state.
F.
If a bridge assurance port fails to receive a BPDU after a timeout, the port is put into an error
disabled state.
Explanation:
E ? port is puting into a BA_inconsistance state
According to:
https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/layer2/521_n1_1/b_5k_Layer2_Config_521N11/b_Nexus_5000_Layer2_Config_521N11_chapter_01001.html
Understanding Bridge Assurance
You can use Bridge Assurance to protect against certain problems that can cause bridging loops in the network. Specifically, you use Bridge Assurance to protect against a unidirectional link failure and a device that continues to forward data traffic when it is no longer running the spanning tree algorithm.
Note
Bridge Assurance is supported only by Rapid PVST+ and MST. Legacy 802.1D spanning tree does not support Bridge Assurance.
Bridge Assurance is enabled by default and can only be disabled globally. Also, Bridge Assurance can be enabled only on spanning tree network ports that are point-to-point links. Finally, both ends of the link must have Bridge Assurance enabled.
With Bridge Assurance enabled, BPDUs are sent out on all operational network ports, including alternate and backup ports, for each hello time period. If the port does not receive a BPDU for a specified period, the port moves into the BLOCKING state and is not used in the root port calculation. Once that port receives a BPDU, it resumes the normal spanning tree transitions.