In 1850 there was a large snowshoe rabbit population in Manitoba, Canada. Over the years, the winter coloration (the color of the rabbit's fur) of the surviving rabbit population changed. The graph shows the change in winter coloration of rabbits between 1850 to 2000. Based on the data, we could hypothesize that A) the winters are longer in length. B) the snowshoe rabbit has migrated to another area. C) the amount of snow cover varied over the years. D) more snowshoe rabbit predators have moved into Manitoba.