The correct option is C Seasonal variation
Seasons are a result of the Earth’s slight axis as it revolves around the sun. This changes the intensity and duration of sun’s heat which in turn affects the temperature of different regions on Earth. This coupled with precipitation over a period of time in a given ecological place has given rise to the major biomes. A biome is thus a cumulation of the various interactions between different ecosystems. Each biomes have their distinct weather, rainfall, animals and plants.