Which is a correct statement about bridge port roles in STP?

A. Every switch, excluding the root bridge, must have at least one root port.
B. Every switch, including the root bridge, must have at least one designated port.
C. Every switch, excluding the root bridge, must have at least one alternate port.
D. Every switch, including the root bridge, must have at least one backup port.

A. Every switch in the network segment must have at least one root port. This is the port that leads back to the root bridge. The root bridge will have a designated port on the adjacent link.