What do you clean your hands with - Joker of the day

The teacher asked: “John, what are the four basic elements in nature?”

John answered: “Fire, air, soil and… and…”

“And what?”, the teacher asked. “Try to remember!”

“And… and…”, John was embarrassed.

The teacher knew that his pupil couldn’t remember that the fourth element was water. Therefore, he gave a hint: “What do you clean your hands with?”

John excitedly screamed: “Soap!”