- Statement A is incorrect. Revenue farming (Ijarah system) became prevalent in Bengal, particularly during the time of Murshid Quli Khan, who rationalized and expanded its use in the early 18th century. Ali Mardan Khan is historically known for his association with the Mughal period, specifically for public works like canals (like the Delhi branch of the Yamuna Canal) during the reign of Shah Jahan, and not for introducing revenue farming in Bengal. - Statement B is correct. Maharaja Ranjit Singh, the ruler of the Sikh Empire, modernized his army extensively. He employed European officers (like Ventura, Allard, Court, Gardner) to train his troops and set up modern foundries in Lahore and Amritsar to manufacture cannons and other weaponry. - Statement C is correct. Sawai Jai Singh II of Amber (Jaipur) was a renowned scholar, astronomer, and city planner. He was keen on advancements in science and technology and sponsored the translation of several important European works on mathematics and astronomy into Sanskrit, including Euclid's 'Elements of Geometry' (referred to here as 'Elements of Colometry'). - Statement D is correct. Sultan Tipu Sultan of Mysore, despite his conflicts with the Marathas and the British, was known to maintain good relations with the Sringeri Matha, a prominent Hindu religious institution. Historical records show that he provided financial assistance for the rebuilding of the Sringeri temple, which had been attacked by Maratha forces, and contributed money for the consecration and installation of the idol of Goddess Sharada.