Token currency was introduced due to a severe shortage of silver and heavy military and administrative expenses.

Bronze and copper coins were given the same face value as silver tankas, but lack of royal monopoly on minting resulted in rampant counterfeiting.

The economic crisis deepened as people paid their land revenue in fake copper coins and hoarded gold and silver.

Muhammad bin Tughlaq is often remembered in history as a 'mixture of opposites' due to his visionary yet poorly executed administrative experiments, which also included the transfer of the capital to Daulatabad.

Option A (Alauddin Khalji) is incorrect because he is famous for his market control regulations, price fixation, and revenue reforms rather than token currency.

Option C (Firoz Shah Tughlaq) is incorrect as he is known for public works, canal construction, and the imposition of Sharia-approved taxes.

Option D (Iltutmish) is incorrect because he introduced the silver Tanka and copper Jital as the standard coins of the Delhi Sultanate.