Answer:
C. The knight in the Emperor's court.
Step-by-step explanation:
It is the knight in the Emperor's court who opposes Faustus. When Faustus visits the emperor's court, he meets the emperor, and he is able to conjure Alexander the Great and his lover, in order for the Emperor to meet them. The knight was skeptical of this, and made fun of Faustus. As Faustus performs this feat, the knight continues to be rude and decides to attack Faustus. He is able to attack him later as Faustus is leaving court, but cannot kill him due to Faustus's immortality.