As per the 2011 Census of India, among the options provided (which are all states), Bihar had the highest population density. The population density figures for the states listed in 2011 were approximately: - Bihar: 1106 persons per sq km - West Bengal: 1028 persons per sq km - Kerala: 860 persons per sq km - Uttar Pradesh: 829 persons per sq km While Union Territories like Delhi (around 11,320) and Chandigarh (around 9,252) had much higher densities, the question asks for states. Among the given states, Bihar had the highest population density.