The correct answer is option 2: Treaty of Madras. The first Mysore War was fought between the British and Hyder Ali from 1767 to 1769. The conflict arose due to the expansionist ambitions of Hyder Ali, who wanted to establish control over the British holdings in southern India. The Treaty of Madras, signed in 1769, marked the end of the war. This treaty was negotiated in the city of Madras (now Chennai) and resulted in a peace agreement between the two parties. It established certain terms and conditions for maintaining peace, such as the return of captured territories and prisoners. It is important to note that the other options mentioned do not accurately correspond to the conclusion of the first Mysore War.