The best response would be:
The soliloquy gives the audience information that they would not have known otherwise, helping them understand and enjoy what happens next.
This response captures how Oberon's speech provides crucial context for the events that are about to unfold in the play, particularly regarding his plans to use the magical juice on Titania. It enhances the audience's understanding of the character's motives and sets the stage for the ensuing conflicts and resolutions.