Why does the author call the Mayan homeland both a “seasonal tropical forest” and "seasonal desert”?

• To illustrate how the climate of the Mayan homeland varied from region to region
• To explain how the climate of the Mayan homeland is similar to that of a jungle or tropical rainforest
• To emphasize the vast size of the area that comprised the Mayan homeland in ancient times
• To make the point that the Mayan homeland is climatically more complex than is generally assumed

This is a multiple choice.