The social system of the Harappans was fairly egalitarian, which means that there was a level of equality among the people in their society. This means that there was no strict hierarchy or class system based on wealth, caste, or occupation. Unlike option 2 and option 4, there is no evidence to suggest that the Harappans relied on slave labor or had a caste-based social structure. Option 3 suggests that their social system was based on color (varna), which is not supported by archaeological evidence. It is important to note that our understanding of the Harappan social system is limited due to the lack of written records, but based on archaeological remains and artifacts, the consensus is that their society generally had a relatively equal distribution of resources and power.