Typically he leaves the stage. That is the Protagonist's role during the First Stasimon. Option D is correct.
A stasimon in Greek tragedy is a stationary song, composed of strophes and antistrophes and performed by the chorus in the orchestra.
According to Aristosteles, each choral song (or melos) of a tragedy is divided into two parts, first the parodos (Ancient Greek: πάροδος) and then the stasimon.
