Modified deficit round robin supports which of these functionalities？（）

A.An IPv4-compatible tunnel is a static tunnel， but an 6to4 tunnel is a semiautomatic tunnel.
B.The deployment of a IPv4-compatible tunnel requires a special code on the edge routers， but a 6to4 tunnel does not require any special code.
C.An IPv4-compatible tunnel is typically used only between two IPv6 domains， but a 6to4 tunnel is used to connect to connect two or more IPv6 domains.
D.For an IPv4-compatible tunnel， the ISP assigns only IPv4 addresses for each domain， but for a 6to4 tunnel， the ISP assigns only IPv6 addresses for each domain.

A.HTTP
B.IP multicast
C.TCP flows with dynamically assigned port numbers
D.non-UDP protocols

A.802.1D bridges do not relay BPDUs.
B.802.1w bridges do not relay BPDUs.
C.802.1D bridges only relay BPDUs received from the root.
D.802.1w bridges only relay BPDUs received from the root.