Concept:Bihar was created as a separate province by the British government in 1912 after being carved out from Bengal. The key date for its establishment is 22 March 1912.Explanation:The British decided to split the Bengal Presidency in 1911. On 22 March 1912, the new province of Bihar and Orissa was formed. Orissa later separated in 1936. Bihar was officially established on that day. It became a state under the Indian Constitution on 26 January 1950. The southern part of Bihar was carved out to form Jharkhand on 15 November 2000. Bihar Day is celebrated annually on 22 March. Among the given options, only 1912 matches the historical fact. Therefore, the correct option is B (1912).Answer:B. 1912