During the Empire, trade greatly expanded between India and other parts of the world. Indian merchants often served as middlemen between traders from the West and those from. was an important trade good, and it often passed through Indian hands before moving to other regions. This growth in trade resulted in wealth and the development of India's first system.

Expanding trade brought merchants greater wealth and created a need to store money, make payments, and lend funds. These activities helped develop India's first banking system, so the correct choice is banking. Taxation and civil service are forms of government organization, not systems created to support merchants' financial transactions.

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