The correct answer is: c) Loamy.
Alluvial soils are typically loamy, meaning they are a mixture of sand, silt, and clay. Loamy soils are well-drained and have good water retention, making them ideal for agriculture.
Sandy soils are composed mostly of sand, which makes them loose and well-drained. However, they do not hold water well, so they can be difficult to grow crops in.
Clayey soils are composed mostly of clay, which makes them dense and poorly drained. They can hold water well, but they can also be difficult to work with and can become compacted.
Rocky soils are composed mostly of rocks, which makes them difficult to cultivate. They are also not very fertile, so they are not ideal for agriculture.