Explanation:
'Diwan-E-Arj' was a military department established by Ghiyasuddin Balban, responsible for army organization and defense. Other important departments during the Delhi Sultanate include: Diwan-i-Wizarat (Finance), Diwan-i-Insha (Correspondence), Diwan-i-Mustakharaj (Revenue Arrears, Alauddin Khilji), Diwan-i-Riyasat (Commerce, Alauddin Khilji), Diwan-i-Kohi (Agriculture, Muhammad Bin Tughlaq), Diwan-i-Bandgan (Slaves, Firoz Tughlaq), Diwan-i-Khairat (Charity, Firoz Tughlaq), Diwan-i-Isthiaq (Pensions, Firoz Tughlaq). [60-62nd BPSC Prelims Exam 2017]