Which reserved AS number or range of numbers is used for backward compatibility between old BGP peers using 16-bit AS number and new BGP peers using 32-bit AS number?
A. AS 65001 to 65535
B. AS 65512 to 65535
C. AS 12345
D. AS 23456
E. AS 64001
Which reserved AS number or range of numbers is used for backward compatibility between old BGP peers using 16-bit AS number and new BGP peers using 32-bit AS number?