The Peanut router is able to successfully ping the Serial 0 and Ethernet 0 interface of the Popcorn router, but a ping issued to the Ethernet 1 interface fails. Based on the above output, what are the potential causes of this problem?（）

• A、The Popcorn router is not forwarding RIP updates.
• B、The Popcorn router did not include network 192.168.12.0 in its routing configuration.
• C、The Ethernet1 interface of the Popcorn router is shutdown.
• D、The clockrate is not present in the configuration of one of the routers.
• E、The Serial interface of the Popcorn router is not operating.