I want to do MBA in HR. Which is a better option among single specialisation and double specialisation?

Single will be more effective as you will get the whole picture of your specialisation.

I will suggest you to do MBA in HR or any other specializations. The degree programme in Maters in Business Administration is one of the most jobs provider educational degree course in the world. If you are looking for best university for MBA course, I would say Lovely professional University is bes