Correct choice is (b) Formation of Alluvial Soil
The explanation: In prehistoric periods, the area starting from the Himalayas to Vindhya mountains is used to in the form of depressions with water flowing over it. But over the ages these depressions got filled with fine silt particles, thereby forming into alluvial soil. So the rivers present in this area of north India flow in alluvial soil carrying silt. So, therefore the artificial channels carrying water from such rivers thus have to carry silt sediment.