Answer:
(Enter CLARENCE, guarded, and BRAKENBURY)
Step-by-step explanation:
Stage directions usually indicate the movements, positions and tones of the actors, as well as the sound and lighting effects the author considers necessary to execute the play correctly.
In the excerpt from "Richard III," the author William Shakespeare includes stage directions to instruct how the play should be performed. In that respect, he indicates that Clarence and Brakenbury must enter the stage - the former surrounded by guards.