Question

Correct the text by inserting one comma.

In 2012, three national power grids in India failed so hundreds of millions of
people were left without power.

Answer 1

The comma goes before “so” because ’so’ is a connective word.

Answer 2

A comma belongs before the word "so," because this is a conjunction that introduced a new independent clause.

Step-by-step explanation:

I hope this helps.