MS Excel: How to match rows that have 2 separately matching columns
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I have 4 columns, A through D. I need to find rows where column C is the same in each row, and column D is the same in each row. It would be best to have a True or False value placed in column E. VBA or a formula works, although I'd think something like this is do-able with a formula.

For example, I have the following:
 
Row 1   XX    123   XYZ  
Row 2   XX    234   XYZ  
Row 3   XX    234   YZX  
Row 4   XX    234   YZX  

In this example, Column E would be False for Rows 1 and 2 and True for Rows 3 and 4.

Thank you!