So you finally made it.
The end of your journey is at hand.
In a few moments, you will meet the king.
You will determine the future of this world.
You will be judged.
The Choice is the 73rd track in the Undertale Soundtrack. It plays while Sans judges the protagonist, during Asgore's speech at the end of his battle, and when Sans "spares" the protagonist during his battle in the Genocide Route at a slightly slower speed.
- Crazy Undertale Music Secret - What "The Choice" Is Hiding - YouTube