Final answer:
Harappa and Mohenjo-Daro, ancient cities of the Indus Valley Civilization, were known for their sophisticated urban planning and architecture, but not for having a strong centralized government. They likely had a system of city-states or some form of diffused governance. The correct option is D.
Step-by-step explanation:
The ancient civilizations of Harappa and Mohenjo-Daro were known for many significant achievements, some of which include the grid patterns of their streets, drainage and sanitation systems, and great walls and fortresses.
These attributes reflect the high level of urban planning and architectural sophistication that characterized these civilizations. Yet, one thing they were not known for is D) Strong centralized governments.
This is largely because the Indus Valley Civilization, of which both Harappa and Mohenjo-Daro were part, exhibited characteristics of a diffused governance structure or a system of city-states, rather than a strong, centralized government.
As such, while there is evidence of some form of administrative control, it does not seem to have been carried out by a central autocratic power. The correct option is D.
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