Which command set should you run?

You have two Cisco Nexus 7700 Series switches named SwitchA and SwitchB. You use the Rapid PVST+ protocol. You must configure the switches as the STP root switches for VLANs 100 to 200.

Which command set should you run?
A . SwitchA(config)# spanning-tree vlan 100-200 priority 61440
SwitchB(config)# spanning-tree vlan 100-200 priority 61440
B . SwitchA(config-if)# spanning-tree guard root
SwitchB(config-if)# spanning-tree guard root
C . SwitchA(config-if)# spanning-tree cost 100
SwitchB(config-if)# spanning-tree cost 100
D . SwitchA(config)# spanning-tree vlan 100-200 root primary
SwitchB(config)# spanning-tree vlan 100-200 root secondary

Answer: D