The correct answer is A. 1803.
The Battle of Assaye was fought on 23 September 1803, during the Second Anglo-Maratha War. The British East India Company army, led by General Arthur Wellesley, defeated the Maratha army, led by Holkar. The battle was fought near the village of Assaye in the Deccan Plateau of India.
The British army was outnumbered by the Maratha army, but they had superior firepower. The British also had better discipline and training. The battle was a hard-fought one, but the British were eventually victorious.
The Battle of Assaye was a significant victory for the British East India Company. It helped to secure British control of the Deccan Plateau. The battle also made Arthur Wellesley a national hero in Britain.
Option B is incorrect because the Battle of Assaye was not fought in 1804.
Option C is incorrect because the Battle of Assaye was not fought in 1805.
Option D is incorrect because the Battle of Assaye was not fought in 1807.