Final answer:
Cyclones are classified as such when their wind speeds reach or exceed gale force. The Coriolis force determines their rotation direction, varying between hemispheres. So the correcct answer is Option D.
Step-by-step explanation:
Cyclones are termed as such when their winds equal or exceed d. gale force. These storm systems, such as hurricanes, typhoons, and tropical storms, which are all regionally specific terms for tropical cyclones, are characterized by their rotation patterns, low pressure centers, strong winds, and heavy rains. The Coriolis force is responsible for the direction of rotation of these cyclones, causing hurricanes in the Northern Hemisphere to rotate in a counterclockwise direction and those in the Southern Hemisphere to rotate in a clockwise direction. Tropical cyclones occur over warm ocean water and their formation is closely related to certain temperature thresholds and atmospheric conditions, which are influenced by the Coriolis effect and Newton's Universal Law of Gravitation.