Starting from the wild mustard Brassica oleracea, breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Therefore, which of the following statements is correct?
-Heritable variation is low in wild mustard otherwise this wild strain would have different characteristics.
-In this wild mustard, there is enough heritable variation to permit these different varieties.
-In wild mustard, most of the variation is due to differences in soil or other aspects of the environment.
-Natural selection is rare in wild populations of wild mustard.