Since There Is No Written Evidence Available,what Other Evidence Have

Since there is no written evidence available,what other evidence have scholars used to explain the social stratification of the Harappan Era society?

A) Scholars made assumptions based on studying other societies that existed at the time.
B) India and Mesopotamia were involved in trade, and Sumerian writing describes India's social system.
C) Since Mesopotamia and India were involved in trade, it is assumed that small shops and craftsmen existed and that wealth and occupational diversity were associated with these.
D) Scholars made assumptions based on studying evidence of societies that existed after the Harappan.
E) Archaeologists have studied the residences of different sizes and complexity, which indicates classes based on wealth.