Respuesta :
The correct answer is sewer system. Unlike other river valley civilizations like Egypt, the Indus Valley Civilization had greatly developed their sewage system which increased the hygiene and the lifestyle of the people, which in turn enabled many other things to develop and prosper and the civilization became one of the biggest in the world.
Answer:
sewer system
streets in a grid of rectangles
water storage systems
Explanation: I think im right but not sure