Which two are characteristics of an IPv6 multicast address？（）
- AFirst （most significant ） octet is FF in hex
- BStarts with a prefix of FE80 to FEBF in hex
- CStarts with a prefix of FECO to FEFF in hex
- DSecond octet contains a 4-bit multicast scope field
- ELast 64 bit contains the modified MAC address of the Ethernet interface
- FIs allocated from the unicast address space