问题：

[单选]

Refer to the exhibit. Catalyst R is the root bridge for both VLAN 1 and VLAN 2. What is the easiest way to load-share traffic across both trunks and maintain redundancy in case a link fails，without using any type of EtherChannel link-bundling？ （）

A . Increase the root bridge priority （increasing the numerical priority number） for VLAN 2 on Catalyst D so that port D2 becomes the root port on Catalyst D for VLAN 2
B . Decrease the port priority on R2 for VLAN 2 on Catalyst R so that port D1 will be blocked for VLAN 2 and port D2 will remain blocked for VLAN 1
C . Decrease the path cost on R2 on Catalyst R for VLAN 2 so that port D1 will be blocked for VLAN 2 and port D2 will remain blocked for VLAN 1
D . Increase the root bridge priority （decreasing the numerical priority number） for VLAN 2 onCatalyst R so that R2 becomes the root port on Catalyst D for VLAN 2