The correct answer is: a) Alluvial soil
Alluvial soil is the most predominant soil type found in Andhra Pradesh. It is a type of soil that is formed by the deposition of sediments from rivers and streams. Alluvial soils are typically rich in nutrients and organic matter, making them ideal for agriculture.
Red soil is a type of soil that is formed in tropical and subtropical regions. It is characterized by its reddish-brown color, which is due to the presence of iron oxide. Red soils are typically poor in nutrients and organic matter, making them less suitable for agriculture than alluvial soils.
Black soil is a type of soil that is formed in semi-arid and sub-humid regions. It is characterized by its dark color, which is due to the presence of organic matter. Black soils are typically rich in nutrients and organic matter, making them ideal for agriculture.
Laterite soil is a type of soil that is formed in tropical and subtropical regions. It is characterized by its high iron and aluminum content, which gives it a reddish-brown color. Laterite soils are typically poor in nutrients and organic matter, making them less suitable for agriculture than alluvial soils.