The correct answer is Three-tier. Explanation & Key Takeaways: • The Balwantrai Mehta Committee was appointed by the Government of India in January 1957 to examine the working of the Community Development Programme (1952) and the National Extension Service (1953). • The committee submitted its report in November 1957 and recommended the establishment of the scheme of Democratic Decentralization, which eventually came to be known as Panchayati Raj. • The specific recommendation was for a three-tier Panchayati Raj system consisting of the Gram Panchayat at the village level, the Panchayat Samiti at the block level, and the Zila Parishad at the district level. • The Gram Panchayat was to be constituted with directly elected representatives, whereas the Panchayat Samiti and Zila Parishad were to be formed with indirectly elected members. • The committee envisioned the Panchayat Samiti as the executive body and the Zila Parishad as the advisory, coordinating, and supervisory body, chaired by the District Collector. • Following these recommendations, Rajasthan became the first state to adopt the system, inaugurated in Nagaur district on October 2, 1959, by the then Prime Minister Jawaharlal Nehru. Related Concepts: • Two-tier system: • This was recommended by the Ashok Mehta Committee in 1978, which suggested a Zila Parishad at the district level and a Mandal Panchayat (representing a group of villages) to replace the three-tier structure. • Four-tier system: • The G.V.K. Rao Committee (1985) observed that the Panchayati Raj had become grass without roots due to bureaucratization and suggested a four-tier structure including State-level Council, Zila Parishad, Mandal Panchayat, and Gram Sabha. • L.M. Singhvi Committee (1986): • This committee recommended that Panchayati Raj institutions should be constitutionally recognized and protected to ensure regular elections and financial autonomy. • 73rd Constitutional Amendment Act, 1992: • This act gave constitutional status to the Panchayati Raj system, mandating a three-tier system for all states with a population of over 20 lakh, adding Part IX and the Eleventh Schedule to the Constitution of India.