The correct option is D Maintaining an army of their own.
<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->
Iqtas meant the revenue districts. They were looked after by the nobles, who were also the military commanders. They were known by different names such as Iqtadars, Muqti and Wali. The main duties of the Iqtadars in the Delhi Sultanate were to collect revenue, look after the judicial administration of their divisions, and maintain an army of their own.