The Indus and Ganges Rivers form a fertile plain. This fertile plain gave rise to the important civilization known as the Indus Valley civilization and cities, such as Harappo and Mohenjo Daro. The arrival of the nomadic Aryan tribes to the Valley of the Indus River is related, according to some historians, for the decline of the Indus River civilization.
B. rust belt is the right answer
C rounds to 6 and the rest found to 5.
