Final answer:
The correct answer is D. air sinks, which creates a calm and clear area in the eye of a hurricane that contrasts with the intense storm activity surrounding it.
Step-by-step explanation:
Inside the eye of a well-developed hurricane, the correct answer is D. air sinks. The eye of the hurricane is characterized by a distinctive calm and clear area surrounded by a powerful, spiraling storm. This phenomenon occurs because air that flows into the hurricane's low-pressure center rises and cools, forming clouds and precipitation around the eye wall. In the center, or eye, the air is instead subsiding, or sinking, which is why the eye is often clear and free of clouds. This subsiding air is associated with high pressure aloft and contributes to the characteristic calm weather in the eye, contrasting with the intense wind and rain found in the eye wall just outside the eye.