I have the following exported date:

A1 - 100 B1 - A C1 - $100
A2 - 200 B2 - B C2 - $50
A3 - 300 B3 - C C3 - $0
A4 - 100 B4 - A C4 - $0
A5 - 300 B5 - C C5 - $0

I would like to lookup the value in column C and where the value is $0, I would like to then lookup columns A and B and highlight the rows that have a $0 value in column C but do not highlight a row where the value in column C is $0 and column A and B are identical that have a value greater than $0 in column C.

For example: do not highlight the row A4 as although the value in column C is $0, column A and B are identical to row A1 and A1 has a value in column C that is greater than $0.

Rows A3 and A5 should be highlighted as values in column C are $0 and values in columns A and B are identical.

Hope this makes sense.