An engineer is troubleshooting IS-IS configuration between two areas. IS-IS Area-A network 30.1.1.0/24 is leaked into IS-IS Area-A. R2 is failing to filter the route updates from network 10.1.1.0/24. Which configuration must the engineer apply to resolve the issue?

A. R2(config)# ip prefix-list List2 seq 5 deny 10.1.1.0/24
R2(config)# interface fastethernet 0/0
R2(config-if)# ip router isis 100
R2(config-if)# router isis 100
R2(config-router)# distribute-list gateway List2 in
B. R2(config)# ip prefix-list List1 seq 3 deny 10.1.1.0/24
R2(config)# ip prefix-list List1 seq 5 permit 30.1.1.0/24 ge 25 1e
R2(config)# ip prefix-list List1 seq 10 permit 0.0.0.0/le 32
R2(config)# interface fastethernet 0/0
R2(config-if)# ip router isis 122
R2(config-if)# router isis 122
R2(config-router)# distribute-list prefix List1 in
C. R1(config)# ip prefix-list List2 seq 5 deny 10.1.1.0/24
R1(config)# interface fastethernet 0/0
R1(config-if)# ip router isis 100
R1(config-if)# router isis 100
R1(config-router)# distribute-list gateway List2 in
R (config-if)# router isis 150
R1(config-router)# distribute-list route-map Map1 in
D. R2(config)# access-list 101 deny ip any 10.1.1.0 0.0.0.127
R2(config)# access-list 101 permit ip any 30.1.1.0 0.0.0.63
R2(config)# access-list 101 deny ip any 0.0.0.0 0.0.0.0
R2(config)# interface fastethernet 0/0
R2(config-if)# ip router isis 121
R2(config-if)# router isis 121
R2(config-router)# distribute-list 101 in

Answer: Option C.

Explanation:

Reference: https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_isis/configuration/15-mt/irs-15-mt-book/isis-inboundfiltering.html