Answer:
Drought, because the ecosystem is very dry
Step-by-step explanation:
Since the big portion of the south western territory in United States would be made up of dessert that means on an average, this territory would have few rainfall if we compared to the other states due to this, this territory would become very dry as because there is the scarcity of the water and also there is less vegetarian that could survive in this territory
Therefore the second option is correct