Which was the last state/region annexed by the British in 1856 which was expected to complete the process of territorial annexation of India?

Awadh

The correct answer is Option 2 - Awadh

The last state/region to be annexed by the Britishers was Awadh, in 1856.

The British became increasingly interested in acquiring the territory of Awadh. They felt that the soil there was good for producing indigo and cotton, and the region was ideally located to be developed into the principal market of Upper India. By the early 1850s, moreover, all the major areas of India had been conquered: the Maratha lands, the Doab, the Carnatic, the Punjab and Bengal. The takeover of Awadh in 1856 was expected to complete a process of territorial annexation that had begun with the conquest of Bengal almost a century earlier.