The correct answer is: b) Hilly regions.
Turmeric, ginger, and black pepper are all tropical plants that require warm, humid climates to grow. They are typically cultivated in hilly regions with well-drained soil. These regions provide the ideal conditions for the growth of these spices, as they offer a combination of warm temperatures, high humidity, and plenty of rainfall.
Coastal plains are typically too dry and hot for the cultivation of these spices. Dryland areas are also too dry, and they often lack the necessary nutrients in the soil. Areas with high rainfall are more suitable for the cultivation of these spices, but they can be prone to flooding, which can damage the plants.
Hilly regions offer the best combination of conditions for the cultivation of turmeric, ginger, and black pepper. The warm temperatures, high humidity, and well-drained soil in these regions provide the ideal environment for these plants to grow.