What are two important differences between OSPFv2 and OSPFv3? (Choose two.)
A. Only OSPFv3 provides support for IPv6.
B. Only OSPFv3 automatically chooses a router ID for the local device.
C. Only OSPFv3 automatically enable interfaces when you create them in device configuration mode.
D. Only OSPFv3 supports multiple OSPF instances on a single link.
E. Only OSPFv3 automatically detects OSPF neighbors on an NBMA interface.
My mistake, it should be: AD
An OSPFv3 process can be configured to be IPv4 or IPv6. The address-family command is used to determine which AF will run in the OSPFv3 process. Once the address family is selected, you can enable multiple instances on a link and enable address–family-specific commands.
AC
An OSPFv3 process can be configured to be IPv4 or IPv6. The address-family command is used to determine which AF will run in the OSPFv3 process. Once the address family is selected, you can enable multiple instances on a link and enable address–family-specific commands.
AD
http://www.ciscopress.com/articles/article.asp?p=2294214&seqNum=4
This section describes OSPFv3, the IPv6-capable version of the OSPF routing protocol, including its operations, configuration, and commands.
With the OSPFv3 address families feature, you may have two device processes per interface, but only one process per AF. If the IPv4 AF is used, an IPv4 address must first be configured on the interface. For IPv6 AF it is enough, if only IPv6 is enabled on the interface, as OSPFv3 uses link-local addresses. A single IPv4 or IPv6 OSPFv3 process running multiple instances on the same interface is not supported.