The correct answer is: a) Lachit Borphukan.
Lalit Borphukan was an Ahom general who led the Ahom army to victory against the Mughals in the Battle of Saraighat in 1671. He was also the commander-in-chief of the Ahom army during the Battle of Itakhuli in 1674.
Badan Chandra Borphukan was an Ahom general who served as the commander-in-chief of the Ahom army from 1769 to 1770. He was defeated by the British in the Battle of Guwahati in 1769.
Purandar Singha was the Ahom king from 1769 to 1780. He was defeated by the British in the Battle of Guwahati in 1769.
Maniram Dewan was an Ahom minister who served as the dewan of the Ahom kingdom from 1794 to 1799. He was executed by the Ahom king for his involvement in a conspiracy against the king.
Lalit Borphukan was the most successful Ahom general against the British. He led the Ahom army to victory in the Battle of Saraighat, which is considered to be one of the most important battles in Indian history.