The correct option is A Sixth Schedule
The Autonomous District Councils are institutions of local governance created under the Sixth Schedule of the constitution of India with Executive, Legislative and Judicial powers. The Sixth schedule was designed to protect tribal identity, preserve tribal custom and tradition. The Khasi Hills Autonomous District Council was constituted under the sixth schedule to the constitution of India. It consists of 30 members out of which 29 are elected on the basis of adult suffrage and one member is nominated by the Governor.