What is the reason for running spanning tree in a Cisco Single-Site Secure Network Foundation solution?

A.
to allow management of all network devices

B.
to aggregate logical network groups together at one central point

C.
to protect the network in case someone inadvertently creates a physical loop in it

D.
to ensure that if a device fails another device will automatically take over for it

E.
to connect like devices, such as phones or computers, in logical network groups