D. Nobody really knows what the question is.

Yes! Yes, Yes, Yes!!!

42 is The Answer to the great question of Life, the Universe, and Everything. The problem is that nobody really knows what the question is.

The Answer was discovered by the great computer Deep Thought.

There is a theory that states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

There is another that states that this has already happened.

From The Hitchhiker’s Guide to the Universe, by Douglas Adams and The Hitchhiker’s Guide Project.

Now, what was the question again?