The answer is C, speciation.
Let's say someone dropped 100 lions in the African savanna and 100 lions in the mountains. The mountain lions would evolve and adapt differently than the savanna lions.
The mountain lions might develop lighter fur for camouflage or larger lungs to get more oxygen from the thinner air, and the savanna lions might have to be a lot stealthier since there's no cover in the open plains.
