Correct Option (D):
Tipu Sultan, the ruler of Mysore (1782-1799), is credited with establishing diplomatic relations on modern lines. He dispatched embassies to various foreign countries, including France, Turkey, and Egypt, primarily to forge alliances against the British. His efforts represented an early instance of an Indian ruler engaging in international diplomacy with a contemporary, strategic outlook, also reflected in his adoption of European military tactics and modern weaponry.
Incorrect Options:
Haider Ali, Tipu Sultan's father, undertook significant military reforms but did not establish diplomatic embassies on modern lines.
Mir Qasim, the Nawab of Bengal, focused predominantly on internal administrative and military reorganization rather than initiating foreign diplomatic missions.
Shah Alam II, a Mughal emperor, reigned during a period of significant decline and was largely under the influence or control of the British, rendering him unable to pursue independent foreign policy or establish modern embassies.