Answer:
Tectonic shift
Step-by-step explanation:
Mohenjo-Daro was regarded as one of the most advanced early civilization in the world due to their ability to manage their agricultural sector.
Historians believed that somewhere in the past, a tectonic shift Blocked the lower pathway of the Indus Valley River. This blockage somehow prevented the people of Mohenjo-Daro from getting enough water supply for their agriculture. As a result, their economy started to declined and it eventually led to their downfall.