In humid tropical climates, the climate is characterized by year-round warm, muggy, and rainy weather. Average Temperature is about 80 °F. Rains or storms happen almost daily and rainfall ranges from 70 to more than 450 inches a year. Winter is never present. All humid tropical climates are near the equator between the Tropic of Cancer and the Tropic of Capricorn
The reason why the Mongols withdrew form Asia was because of horrible weather conditions and diseases. If I had to pick, I would pick A.) Diseases because A is more severe then the weather conditions.