Option 1: 1 July, 2017 -> GST (Goods and Services Tax) was implemented in India on 1st July 2017 at midnight in a historic session at Parliament's Central Hall. It replaced multiple indirect taxes like VAT, service tax, excise duty, etc., creating a unified tax structure across the country. This was one of the biggest tax reforms in India since independence, aimed at creating 'One Nation, One Tax' system. -> correct