The Seventy Third Constitution Amendment Act, 1992 came into force on

A constitutional amendment does not take effect on the date of its passage or Presidential assent; it comes into force on the date the Central Government formally notifies under the Act's own commencement clause, which can fall weeks after assent.

The Constitution (Seventy-third Amendment) Act, 1992 inserted Part IX (Articles 243 to 243-O) of the Constitution, making the three-tier Panchayati Raj system a constitutional mandate. Parliament passed the Bill in December 1992, and it received Presidential assent on 20 April 1993. The Central Government then notified 24 April 1993 as the date of commencement — which is why 24 April is observed every year as National Panchayati Raj Day.

Checking the offered dates against this timeline:

• 1 June 1993 is the notified commencement date of the companion Seventy-fourth Amendment Act (Part IXA, on Municipalities) — a separate Act with its own notification.

• 2 October 1993 does not correspond to any assent or commencement notification connected with this Amendment.

• 14 January 1992 falls before Parliament even passed the Bill (December 1992), so the Act could not have commenced on a date preceding its own enactment.

Hence, the Seventy-third Constitution Amendment Act, 1992 came into force on 24 April 1993.