A discovery that could provide evidence Against the theory of evolution is: If a primate and a trilobite fossil were found in the same rock layer. Because if that were to happen, then that means that trilobites and primates were from the same time frame, and it also means that primates did not evolve that they were the same since they first lived on the earth.
Selective breeding is when a human or farmer in this case selects two plants or chickens with the best traits in order to get a good yield and quality for the products they are producing. I hope this helps!