A teacher decides to do an experiment with 3 worms for his pupils.
The first worm is put into a jar filled with smoke - the worm dies.
The second worm is put into a jar filled with alcohol - the worm dies.
The third worm is put into a jar filled with chocolate - the worm dies.
The teacher then asks the class what the moral of the story is.
One young girl puts up her hand and says
"If you smoke, drink alcohol and eat chocolate, you won't get worms."