CCNA Practice Exam Test Sample – Question 49

Refer to the exhibit.
Why has this switch not been elected the root bridge for VLAN1?

A. It has more than one interface that is connected to the root network segment.
B. It is running RSTP while the elected root bridge is running 802.1d spanning tree.
C. It has a higher MAC address than the elected root bridge.
D. It has a higher bridge ID than the elected root bridge.

Correct Answer: D
Section: LAN Switching Technologies

The root bridge is determined by the lowest bridge ID, and this switch has a bridge ID priority of 32768, which is higher than the roots priority of 20481.