Final answer:
The climate of the United States is mostly temperate with sub-tropical regions in the south, corresponding to option C. The U.S. features a range of climates from tropical to polar, influenced by geography and latitude.
Step-by-step explanation:
The climate of the United States can best be described as mostly temperate, with sub-tropical regions in the south. This corresponds to option C: Mostly temperate, but sub-tropical regions in the south.
The U.S. experiences a variety of climate types, including type A (tropical) climates in regions like Hawaii and the southern part of Florida, type B (dry or arid) climates in desert regions such as those in the Southwest, and type C (moderate or temperate) climates that are favorable and support the largest human population densities, found mostly in the mid-latitudes. In addition, there are areas with type D (cold or continental) climates characterized by cold winters, especially in the northern interior, and type E (polar) climates found in parts of Alaska.