The first people to migrate to the Indus River Valley were hunters who came from Africa, probably around 40,000 BCE. By about 2300 BCE, the large city of Harappa had been built. Harappa was one of the most developed civilizations in the world in its day. It included the city of Harappa and another big urban area, Mohenjo-daro, about 300 miles away on another section of river. Even though they were far apart, the two cities had striking similarities. Both were laid out with grids of paved streets that made right angles. People built houses out of stone, some of which were three or four stories high. Big fortresses stood near each city to provide protection. The people had weights, measures and a currency, so they could trade. The government may have stored food in case of shortages. They were perhaps the first people to make garments out of cotton. The Harappans used pictographs, drawings and symbols that represented ideas, to write. Both cities had another great invention: sewer systems to carry all human waste out of the city. Almost no other cities had a sewer system at this time. Harappan civilization had all but disappeared by 1700 BCE for reasons that are still unclear. The story of the Harappan civilization is most similar to which of the following?
A
In Ancient Greece, the Mycenaeans made huge advances in engineering and architecture and had a written language. Their society collapsed for unknown reasons in 1100 BCE.

B
The Incan empire did not have many technological advances but covered over 770,000 square miles before it was defeated by Spanish conquistadors in 1533.

C
The Khmer Empire, in modern-day Cambodia, was an enormous Buddhist city with advanced systems of art and architecture. In the 14th century CE it began a long steady decline.

D
The Maori people settled in New Zealand in the 13th century. They developed both a warrior culture and a system of fine and performing arts. The Maori are still around today.