The correct answer is B) Decrease in wind velocity. A decrease in wind velocity would not indicate the approach of a tropical storm. Tropical storms are typically characterized by an increase in wind speed and the formation of other weather patterns such as halos around the sun or moon (A), the presence of cirrus clouds (C), and long, high swells (D). These weather patterns are often precursors to the arrival of a tropical storm, but a decrease in wind velocity would not be a sign of an approaching storm. Instead, it would more likely indicate the storm has already passed or is moving away from the area.