The correct answer is A. 13.14%.
The urban population in Bihar according to 1991 Census was 13.14%. This means that out of the total population of Bihar, 13.14% lived in urban areas. This is lower than the national average of 25.72%. The low proportion of urban population in Bihar is due to a number of factors, including the state’s rural economy, its low literacy rate, and its poor infrastructure.
Option B is incorrect because the urban population in Bihar according to 1991 Census was 13.14%, not 14.13%.
Option C is incorrect because the urban population in Bihar according to 1991 Census was 13.14%, not 10.03%.
Option D is incorrect because the urban population in Bihar according to 1991 Census was 13.14%, not 23.17%.