Refer to the exhibit. STP has been implemented in the network. Switch SW_A is the root switch for the default VLAN. To reduce the broadcast domain， the network administrator decides to split users on the network into VLAN 2 and VLAN 10. The administrator issues the command spanning-tree vlan 2 root primary on switch SW_A.  What will happen as a result of this change？（）

• A、All ports of the root switch SW_A will remain in forwarding mode throughout the reconvergence of the spanning tree domain.
• B、Switch SW_A will change its spanning tree priority to become root for VLAN 2 only.
• C、Switch SW_A will remain root for the default VLAN and will become root for VLAN 2.
• D、No other switch in the network will be able to become root as long as switch SW_A is up and running.