The IO determines which EU Member State (with the exception of Denmark, but including Iceland and Norway) is responsible for treating an application for international protection. This is based on the Dublin III Regulation.
Dublin Regulation
Durable solutions
For each refugee, the UNHCR checks whether a return to the country of origin or local integration in the first country of reception is a (better) option. If the two initial alternatives are not possible, the refugee may be eligible for resettlement.