Explanation:

Both statements 2&3 are correct.
PRI was constitutionalized through the 73rd Constitutional Amendment Act, 1992 to build democracy at the grass roots level and was entrusted with the task of rural development in the country.
Compulsory Provisions

• Organisation of Gram Sabhas;
• Creation of a three-tier Panchayati Raj Structure at the Zila, Block and Village levels;
• Almost all posts, at all levels to be filled by direct elections;
• Minimum age for contesting elections to the Panchayati Raj institutions is 21 years.
• The post of Chairman at the Zila and Block levels should be filled by indirect election;
• There should be reservation of seats for Scheduled Castes/ Scheduled Tribes in Panchayats, in proportion to their population, and for women in Panchayats up to one-third seats;
• State Election Commission to be set up in each State to conduct elections to Panchayati Raj institutions;
• The tenure of Panchayati Raj institutions is five years, if dissolved earlier, fresh elections to be held within six months;
• A State Finance Commission is set up in each State every five years. 

Voluntary

• Giving voting rights to members of the Central and State legislatures in these bodies;
• Providing reservation for backward classes.
• The Panchayati Raj institutions should be given financial powers in relation to taxes, levy fees etc. and efforts shall be made to make Panchayats autonomous bodies.

Hence option 2nd is correct.