The correct option is B British did not help Hyder Ali against Marathas
The treaty of Madras was signed between Hyder Ali and the British. Both agreed to help each other against their common enemy, the Marathas. But in 1771, when the Marathas invaded Mysore, the English did not come forward to help Hyder Ali. The English also captured the French port Mahe which was of great importance to Hyder Ali.