GST was introduced by which amendment act of the Constitution?

101

The correct answer is Option 3 - 101

The Goods and Services Tax (GST) was introduced by the 101st Amendment Act of the Constitution, enacted in 2016.

It's important to note that a prior bill, the 122nd Amendment Bill, was introduced to pave the way for GST implementation. But the final act that enabled GST was the 101st amendment.