Explanation:

Bengal-
The battles of Plassey and Buxar, in which the British defeated the Indian powers, left the company in control of Bengal and a major military and political power in India. In the following decades it gradually increased the extent of the territories under its control, ruling the whole Indian subcontinent either directly or indirectly via local puppet rulers under the threat of force by its Presidency armies, much of which were composed of native Indian sepoys.
Mysore-
Hyder Ali and Tipu Sultan, the rulers of the Kingdom of Mysore, offered much resistance to the British forces. Having sided with the French during the Revolutionary War, the rulers of Mysore continued their struggle against the company with the four Anglo-Mysore Wars. Mysore finally fell to the company forces in 1799, in the fourth Anglo-Mysore war during which Tipu Sultan was killed.
Sind-
Lord Ellen borough as Chairman, Board of East India Company, had recommended to the Prime Minister the conquest of Sindh as early as 1830, thirteen years before he himself, as the Governor General of India, had authorized Charles Napier to do so.
Punjab-
The Second Anglo-Sikh War was a military conflict between the Sikh Empire and the British East India Company that took place in 1848 and 1849. It resulted in the fall of the Sikh Empire, and the annexation of the Punjab and what subsequently became the North-West Frontier Province, by the East India Company.