Ashok Mehta Committee recommended –

Explanation

The Ashok Mehta Committee, formed in 1977, submitted its report in August 1978, in which it recommended a two-tier model in place of the three-tier model of Panchayati Raj. It suggested the formation of Zila Parishad at the district level and Mandal Panchayat for a population of 15,000 to 20,000 (a group of villages).