How Do I Find Mismatched Data?

For a given set of Data in ColumnA, the data in columnB needs to be identical. I'd like to highlight anything that is not identical. I've attached an example sheet to better explain what my goal is.

ColumnA represents the data sets. ColumnB represents the data that should be identical. Columns D and E are repeats of columns A and B, but it's highlighted to show the desired result when the data in columnB are not identical.

I'd really appreciate any help you guys can give me.

Thanks!