Final answer:
The Harappan civilization displayed characteristics of a 'State Society' evident through archaeological discoveries of extensive trade networks and large fortifications, indicating a high level of organization, resource allocation and a strong state authority.
Step-by-step explanation:
The inference that the Harappan civilization reached a 'State Society' level of political complexity can be drawn from archaeological evidence of both extensive trade networks and large fortifications. The presence of extensive trade networks indicates a high level of organization, resource distribution, and negotiation skills which are typically characteristic of state societies. Meanwhile, large fortifications suggest the existence of a strong, central authority to plan and execute such major construction projects. These findings collectively affirm the high degree of complexity in the Harappan state structure.
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