Proof of evolution?

Question

If you had to prove to someone with 1 'fact' why they should believe in evolution, what would you say?

(ex. Wisdom teeth. We needed them before but now they don't fit in our mouths)

Answer 1

your forelimb structure is the same as a frogs

Answer 2

just look at all the different races of people, there would not be white, black, asain, and so on if evolution were not true.