In an IEEE 802.3 Ethernet frame, what is the significance of the DSAP field?

A.	The DSAP field specifies the TCP or UDP port that is associated with the transport protocol.
B.	The DSAP field is only used on United States Department of Defense networks to indicate the information classification level.
C.	The DSAP field is only used in Ethernet II frames.
D.	The DSAP field indicates the network layer protocol.