A.Because the sub-interface numbers of Router A and Router B are inconsistent, so Router A and Router B cannot communicate

B.The sub-interface of Router B cannot learn the MAC address of the sub-interface of Router A

C.The sub-interface of Router A cannot learn the MAC address of the sub-interface of Router B

D.10.0.12.1 can ping 10.0.12.2

A.The role of print is to output the content in the brackets.

B.Python language supports automatic indentation, so you don't need to pay attention when writing code.

C.Python generally executes code from beginning to end in order.

D.Pay attention to the use of comments when writing code to help readers understand the code. Comments start with #.

A.OSPFv2

B.OSPFv3

C.OSPFv4

D.OSPFv1

A.02-03-04-05-06-07

B.00-02-03-04-05-06

C.03-04-05-06-07-08

D.01-02-03-04-05-06

A.3000-3999

B.2000-2999

C.4000~4999

D.6000~6031