A. It supports autonegotiation for both ISL and IEEE 802.1Q trunks.
B. It must be disabled on an interface if you do not want the interface to work as a trunk or start negotiation to become a trunk.
C. It is a point-to-multipoint protocol.
D. It is a point-to-point protocol.
E. It is not supported on private VLAN ports or tunneling ports.