Mongols expanded their empire's extent for largely, geographic reasons. geographic examples would be (select all that are correct).
climate conditions threatened their livestock and fields.
trade restrictions with neighboring empires was thought unreasonable.
deaths of mongol officials seeking business exchanges.
hunger for more territory

Geographic reasons would likely involve the physical attributes of the Earth and the human activities that may affect it. This would include the land area, the water bodies, and the climate conditions. It could also include economic geography like trade with neighboring countries.

Thus, geographic examples that would apply are:

Climate conditions threatened their livestock and fields.
Hunger for more territory
Trade restrictions with neighboring empires was thought unreasonable.