Which of these countries is a part of Scandinavia?

Scandinavia, historically Scandia, part of northern Europe, generally held to consist of the two countries of the Scandinavian Peninsula, Norway, and Sweden, with the addition of Denmark. Some authorities argue for the inclusion of Finland on geologic and economic grounds and of Iceland and the Faroe Islands on the grounds that their inhabitants speak North Germanic (or Scandinavian) languages related to those of Norway and Sweden.

Source: Britannica