Final answer:
Scholars are uncertain about the Indus Valley civilization's government, city planning, reasons for disappearance, and their writing system, due to the indecipherable Indus script hindering a deeper understanding of their culture and administrative systems.
Step-by-step explanation:
Historians and archaeologists still have questions about various aspects of the Indus Valley civilization. Some of the areas where there is a lack of consensus or clarity include:
- The kind of government that existed, with theories ranging from a collection of city-states to regional capitals with some form of centralized authority.
- City planning, which was advanced with grid-like streets and sophisticated water management systems, but the organizational structure behind it is not fully understood.
- The reasons for the civilization's disappearance, including environmental degradation due to deforestation and soil salinization, social and political breakdowns, and potential climate change.
- There is also the enigmatic Indus script, which has not been deciphered, limiting our understanding of their language, culture, and administrative systems.
These gaps in knowledge stem from the inability to read the Indus script, leaving a reliance on archaeological interpretations. Understanding the inner workings and decline of this civilization requires further research and perhaps one day deciphering their writing system.