Upvote:1
It was a case for the Moscow center. They took your copies because you have original documents, thus in this way, they confirm that you have in fact original documents. For further work the Migration only deals with copies. It is understandable for them that you have original docs.
If you did not bring the original docs, they could reject taking only copies. But in fact, and in my case they often accept copies without original docs, it is probably depends on the officer.
Upvote:2
I'm not sure why you were told what you were. All online documentation, including the Short Term Study VISA application page on the UK Government site says you need original documentation only.
In your case, were I you (if you can afford it), I would take the originals, certified copies, and regular copies of all of your documentation. That way, no matter what they ask for, you've covered all of your bases, so to speak.