The correct answer is (a) 1848-49.
The Second Anglo-Sikh War was fought between the British East India Company and the Sikh Empire from December 1848 to February 1849. The war was caused by a dispute over the succession to the Sikh throne after the death of Maharaja Ranjit Singh in 1839. The British supported the claim of Dalip Singh, the young son of Ranjit Singh, while the Sikhs supported the claim of his uncle, Nau Nihal Singh. The war ended with the defeat of the Sikhs and the annexation of the Punjab by the British.
Option (b), 1856-57, is the year of the Indian Rebellion of 1857, also known as the Sepoy Mutiny. This was a major uprising against British rule in India.
Option (c), 1845-46, is the year of the First Anglo-Sikh War. This war was fought between the British East India Company and the Sikh Empire over control of the Punjab region.
Option (d), 1883-84, is the year of the Second Afghan War. This war was fought between the British Empire and the Emirate of Afghanistan.