What characteristic defined the urban culture of early India?

The characteristic that defined the urban culture of early India is the creation of planned cities with sanitation systems. This remarkable urban planning is evidenced in sites such as Mohenjo-Daro and Harappa, which were part of the Indus Valley Civilization. The cities featured well-organized street layouts, drainage systems, and sanitation facilities that indicate a level of sophistication and an understanding of urban infrastructure that was advanced for their time.

This focus on urban planning not only facilitated hygiene and health among the population but also helped in the efficient management of the city, contributing to a sense of community and societal structure. Such developments underscore the importance of environment and public health in early urban centers. The meticulous layout and engineering prowess showcased the capabilities of early Indian society and laid foundational elements for future urban development.

While the other options, like the development of metallurgy, creation of written language, and establishment of centralized government, are significant advancements in human civilization, they are not distinctive characteristics of the urban culture of early India in the same way that the planned cities and their sanitation systems are.