What are two reasons to configure PortFast on a switch port attached to an end host? (Choose two.)

What are two reasons to configure PortFast on a switch port attached to an end host? (Choose two.)

A. to block another switch or host from communicating through the port B. to enable the port to enter the forwarding state immediately when the host boots up C. to prevent the port from participating in Spanning Tree Protocol operations D. to protect the operation of the port from topology change processes E. to limit the number of MAC addresses learned on the port to 1