Thanks for the advice! So admissions committees will usually ignore a postgraduate diploma type qualification? Or just not recognize distance learning?
It's not that committees ignore this type of qualification or do not recognize distance learning (although I think brick and mortar classes are still preferred). It's that you do NOT need to do this. You're looking to shore up an area of your application that is already more than solid. It's not the best use of your effort. There are other aspects of your profile that I'm sure could use improvement. However, academics is NOT one of them.
My only caveat to this would be if you received two D's. In that case it might be a good idea to address what happened in the optional essay. If your passing grades were higher than a D then there's no need to draw attention to what will likely go unnoticed in the big picture of your academic achievements (i.e. 3.7 GPA). Regardless of the grade do NOT waste your time taking additional classes. Good luck on the GMAT!
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