Which additional configuration must be applied to the router to complete the task?

Refer to the exhibit. An engineer is configuring multitopology IS-IS for IPv6 on router R1. Which additional configuration must be applied to the router to complete the task?
A. R1# configure terminal
R1(config)# router isis area2
R1(config-router)# address-family ipv6
R1(config-router-af)# multi-topology
B. R1# configure terminal
R1(config)# router isis area1
R1(config-router)# metric-style wide level-2
R1(config-router)# address-family ipv6
R1(config-router-af)# multi-topology
C. R1# configure terminal
R1(config)# router isis area2
R1(config-router)# metric-style wide
R1(config-router)# address-family ipv6
R1(config-router-af)# multi topology
D. R1# configure terminal
R1(config)# router isis area1
R1(config-router)# metric-style wide level 1
R1(config-router)# address-family ipv6
R1(config-router-af)# multi topology