The correct answer is option 4: 86th Amendment Act.

The 86th Amendment Act, passed in 2002, inserted Article 21A into the Constitution of India. Article 21A provides for the Right to Education, stating that the State shall provide free and compulsory education to all children between the ages of six and fourteen. This amendment aimed to make education accessible and available to all children, as it is considered a fundamental right.

Option 1: 83rd Amendment Act is not the correct answer because this amendment pertains to the reservation of seats for Scheduled Castes and Scheduled Tribes in Lok Sabha and State Legislative Assemblies.

Option 2: 84th Amendment Act is not the correct answer because this amendment pertains to the number of seats in the Lok Sabha to be reserved for the Scheduled Castes and Scheduled Tribes.

Option 3: 85th Amendment Act is not the correct answer because this amendment pertains to the extension of the reservation of seats for Scheduled Castes and Scheduled Tribes in Lok Sabha and State Legislative Assemblies.

Therefore, the correct answer is option 4: 86th Amendment Act.