The correct answer is: A. Alluvial Soil
Alluvial soil is a type of soil that is formed from the deposition of sediment by water. It is typically found in river valleys and deltas. Alluvial soil is very fertile and is often used for agriculture.
Mountain meadow soil is a type of soil that is found in high mountain meadows. It is typically thin and rocky. Mountain meadow soil is not very fertile and is not often used for agriculture.
Saline alkali soil is a type of soil that is found in arid and semi-arid regions. It is typically high in salt and alkali. Saline alkali soil is not very fertile and is not often used for agriculture.
The Upper Indus valley in Ladakh is a high-altitude region with a cold desert climate. The soil in this region is mostly alluvial soil. Alluvial soil is a type of soil that is formed from the deposition of sediment by water. It is typically found in river valleys and deltas. Alluvial soil is very fertile and is often used for agriculture.