Final answer:
In the sub-tropical high-pressure belt, the typical atmospheric behavior is air sinking and diverging, associated with atmospheric stability and clear skies.
Step-by-step explanation:
In the sub-tropical high-pressure belt, the typical atmospheric behavior is characterized by air sinking and diverging. This is because high-pressure systems generally consist of cooler, denser air that sinks towards the surface of the Earth, leading to atmospheric stability and clear skies.
As the air reaches the surface, it diverges, moving away from the high-pressure center. The correct answer to the question is D) Air is sinking and diverging.