The continents of the Earth are constantly in motion . The reason for this motion is the position of the tectonic plates over the mantle of the Earth. The movement of these plates, causes the continents to move. Over the time, these movements becomes substantial and the drifting of the continents is visible. This leads to the formation of the new biomes. The flaura and fauna changes with these movements.
Hence, the correct answer is 'Option A - Biomes'.