Insert Row When value changes in column without Macro

I would like to automatically insert a row at each change in value in one column. See the attached sample. When the value in column C changes, I would like a row inserted. Preferrably without using any macros because they are way beyond my skill level and understanding

why you want to insert the row?
think another way that can solve your problem.

There is no formula for inserting the row without Macro.

I have a large list of 30,000 lines and only want to delete duplicates within a group of these rows based on the same values in one column. It's not critical to have, just a convenience thing.