What should the administrator do to accomplish this?

A network administrator configures MSTP on an ArubaOS switch. The administrator wants to ensure that this switch is always the root for instance 1.

What should the administrator do to accomplish this?
A . Specify priority 15 for spanning tree instance 1.
B . Specify spanning tree cost 0 on all switch ports that connect to other switches that use instance 1.
C . Specify priority 0 for spanning tree instance 1.
D . Specify spanning tree cost 15 on all switch ports that connect to other switches that use instance 1.

Answer: C