Answer:
Natural selection is one of the mechanisms by which an organism evolve. In the natural selection when the trait of an organism allows the organism to grow and reproduce in an environment and nature selects it, it is then passed on to the generations and become permanent.
Artificial selection is also one of the mechanism of evolution in which instead of nature, the selection is made by humans like the breeding experiments on dogs and plant crops.
The artificial selection and natural selection are interlinked as in the artificial selection the trait selected by the humans were also selected by nature like the case of crops, the crossing between desired plants produced results which were useful to the humans but grew and reproduced only when the environment selected it to grow and reproduce.