The question begins by mentioning cheetah variants must have evolved in South America. Then, they spread to Africa. This spread happened when, South America and Africa remained as a unified landmass, so that the cheetahs roamed across the entire stretch without any barriers. Then, the passage throws a contradiction - 2 species which developed in two different topographies, are most likely to exhibit morphological differences, and these differences persist till modern day. They key crux attributed in the above line is because they have been developed at different topographies, the morphological differences is due to the factor mentioned earlier. Further, No two African cheetahs are morphologically distinct, so they must have the same morphology. So, South American cheetah which have moved previously during the united landmass phase, must have become extinct. This leaves us with the African cheetah morphology alone.
Option A is wrong, because it clearly mentions the evolution of cheetah’s happened at South America.
Option B mentions that there is a case, where all the cheetahs of these regions where originally present in South America, and it is this variant, which has spread throughout the areas of Africa. If , all the current species of cheetah in Africa are originally the ones that came from South America, concluding that the migrated species has died, seems to fall apart. Hence, correct answer
Option C - This is out of scope option, as it speaks beyond the context in place. Hence wrong.
Option D - This option goes into the nitty gritty of science involved in these differences and similarities, which is out of scope. Hence, wrong.
Option E - If cheetah variants have evolved in Africa and later died out, then the morphological variation across two different topographical regions would fall apart. Hence, contradictory to the context. Wrong.
Option B