In offices where local clients speak the local languages, both will be tested during the interview.
Hope it helps!
It depends on your interviewer (if he's Danish or not), but it will be probably in Danish. However there will be also parts of the interview in english to test your skills.
Unlike most markets, Scandinavian offices offer positions for people who don't speak the local language. Similar to the Amsterdam or Dubai offices at MBB. This is due to the fact that English is practically omnipresent in the business environment of these markets (as opposed to markets such as Spin, Russia, or Germany, where many clients don't feel comfortable in English).
That being said, you have to align on this with recruiting BEFORE your interview day! And normally it should also be clear from your application documents.
Likely both, but doesn't hurt double-checking beforehand (also, written comms are a good indication)
You will have both, so get prepared
Danish is preferred. However, if you are an international candidate there is the possibility to handle all the process in English, but the positions are less