Need someone who's read Midsummer Night's Dream by Shakespeare!

One theme in A Midsummer Night's Dream is the question of reality: What is real and what is a dream?

How does the ending of the play explore this theme?

A.) Bottom sings a song about dreams and reality in the woods.

B.)Robin makes a final speech that invites the audience to think of the whole play as a dream.

C.)Oberon and Titania put a spell on the lovers so they will think what happened in the woods was a dream.

D.) The "play within a play" uses a dream to predict what will happen to Pyramus and Thisbe.