Explanation:

- Option 3: Hector Munro

- Hector Munro led the British East India Company forces in the Battle of Buxar. The battle took place on October 22, 1764, against the combined forces of Indian rulers. He emerged victorious, solidifying British control in India.

- Option 1: Charles Stuart

- There’s no notable battle leadership by Charles Stuart in the Battle of Buxar. He is unrelated to this context.

- Option 2: Robert Clive

- Clive was a significant British figure in India, particularly known for the Battle of Plassey. But, he did not lead at Buxar.

- Option 4: John William Fortescue

- Known primarily as a British historian, he didn't lead battles for the British East India Company.