Answer:
a) he becomes the authority on the island.
Explanation:
The passage is from Shakespeare's play "Tempest".
Stephano is Alonso's (King of Naples) buttler.
Although Stephano has not become an authority, he has started considering himself as an authority on the island. He is drunk and he thinks that all members of the court have drowned and only he and his friend Trinculo have survived. So he starts considering himself king of the island and joins with Caliban to overthrow Prospero.
Option b is not correct as we already know that such insight is not unexpected from Stephano.
Option D is correct but only when considering the whole context of the play. He furthers the play's subplot of comedy and also presents a glimpse to deposing of Prospero as Duke of Milan.
