Well i don't know what diet and exercise could risk leading to since they are both a pretty healthy thing to do. But tobacco could lead to cancer?
Stopping potential or cut-off potential is defined as the required potential for stopping the removal of an electron from a metal surface when the incident light energy is greater than the work potential of the metal on which the incident light is focused
hope it helps
Carrots are going to be the best choice here. They are rich in vitamin A, which is an awesome powerful amazingly magnificent super hero nutrient! =D