The Company network utilizes the Multiple-instance Spanning Tree protocol in its switched
LAN. Which three statements about the MST protocol (IEEE 802.1S) are true? (Select
three)

A.
To verify the MST configuration, the show pending command can be used in MST
configuration mode.

B.
When RSTP and MSTP are configured; UplinkFast and BackboneFast must also be
enabled.

C.
All switches in the same MST region must have the same VLAN-to-instance mapping, but
different configuration revision numbers.

D.
All switches in an MST region, except distribution layer switches, should have their priority
lowered from the default value 32768.

E.
An MST region is a group of MST switches that appear as a single virtual bridge to
adjacent CST and MST regions.

F.
Enabling MST with the “spanning-tree mode mst” global configuration command also
enables RSTP.

Explanation:
MST is built on the concept of mapping one or more VLANs to a single STP instance.
Multiple instances of STP can be used (hence the name MST), with each instance
supporting a different group of VLANs.
Each could be tuned to result in a different topology, so that Instance 1 would forward on the
left uplink, while Instance 2 would forward on the right uplink. Therefore, VLAN A would be
mapped to Instance 1, and VLAN B to Instance 2.
To implement MST in a network, you need to determine the following:
The number of STP instances needed to support the desired topologies.
Whether to map a set of VLANs to each instance.