RSTP Provides Faster Convergence Than STP

RSTP provides faster convergence than STP. What are causes? (Choose all that apply.)

A) RSTP defines the edge port role. The edge port does not receive and process configuration BPDUs, and not participate in RSTP calculation. The edge port can directly change from the Disable state to the Forwarding state.
B) When the root port fails, the optimal alternate port will become the root port and enter the Forwarding state.
C) In RSTP, when a port is elected as the designated port, it enters the Discarding state. Then the port immediately enters the Forwarding state through the Proposal/Agreement mechanism.
D) In RSTP, when a port receives RST BPDUs from the upstream designated bridge, the port will compare the own stored RST BPDU will the received RST BPDU.
E) When the designated port fails, the optimal alternate port will become the root port and enter the Forwarding state.