Option b is the correct answer Sadak-1-Azam was the term used by Sher Shah Suri for the Grand Trunk Road. The Grand Trunk Road, also known as Uttarapath is among Asia's oldest roads, connecting Central Asia to the Indian subcontinent for over 2,500 years. Extending about 2,400 km, it spans from Teknaf, Bangladesh, to Kabul, Afghanistan, passing through significant cities in Bangladesh, India, and Pakistan. Chahalghani nobles were a group of forty leading Turkish nobles during the reign of Iltutmish. The Corps of Forty (Turkan-e-Chahalgani), initiated by Iltutmish, comprised 40 Turkic slave emirs who aided Delhi Sultanate's governance. They influenced succession and rule, eventually controlling sultans. Sultan Balban dismantled their power, leading to their downfall. This vacuum enabled the rise of the Khalji faction, leading to their overthrow and dispersal. Ain-i-Dahsala was Akbar's land revenue system. Akbar's Dahsala System, introduced by Raj Todar Mal, streamlined land revenue across regions like Lahore to Allahabad. It employed precise measurements with the Bamboo Jarid method and classified lands into categories like Polaj (regularly cultivated), Parauti (recovery), Chachar (intermittent), and Banjar (unused). Grades determined revenue, with one-third share to government, collected in cash or crops, aiding farmers with loans and exemptions in poor yields. Records were established through receipts. Token currency was introduced by Muhammad Tughluq during his rule. Muhammad bin Tughluq's coinage policy included varied coins with imperfect design. In 1330, he issued brass and copper tokens of equal value to gold and silver coins. This step aimed to fund territorial expansion, yet caused devaluation, disrupting trade. Token currency ceased by 1333 due to confusion and counterfeiting.