How did the decline of mughal india aid european traders in the region

The Mughal Empire granted trading rights to Europeans, so the Europeans had already build a large base for trading in the region. The Europeans were allowed to build forts and warehouses for their own protection, and as the Mughal empire weakened the British seized their chance to invade, the British and weakening Mughals fought for power. By the 1700's, The British East India Company controlled most of India forcing it inhabits to slave over them.

Check google mate it's easy