The correct answer is C) Iron Oxides.
Red soils are a type of soil that is rich in iron oxides. They are typically found in tropical and subtropical regions, and they are known for their reddish-brown color. Red soils are well-drained and have a high pH, which makes them ideal for growing crops such as rice, sugarcane, and cotton.
Nitrogen is an essential nutrient for plants, but it is not typically found in high concentrations in red soils. Organic matter is a type of soil that is rich in decaying plant and animal matter. It is important for soil health, as it helps to improve drainage and water retention. Potash is a type of mineral that is essential for plant growth. It is found in many different types of soil, but it is not typically found in high concentrations in red soils.
In conclusion, red soils are rich in iron oxides and are well-drained and have a high pH. They are ideal for growing crops such as rice, sugarcane, and cotton.