The most likely scenario is:
The proportion of white-furred rabbits in the population declines.
As the average temperature increases and winter becomes shorter, it may affect the ability of white-furred rabbits to camouflage themselves in a changing environment, especially if there is less snow cover. Brown-furred rabbits are likely to be better adapted to the warmer climate, as their coloration provides better camouflage in environments with less snow. Therefore, the white-furred rabbits may face increased predation, leading to a decline in their population relative to the brown-furred rabbits.