Boxes around the countries do not necessarily reflect actual water boundaries.
Oceania is the geographical region comprising the Pacific Islands of Micronesia, Melanesia, Polynesia, Australia, and the Malay Archipelago. It is not a continent.
Wondering what happened to the longer list of questions which included American Samoa, the Cook Islands, French Polynesia, etc? The full Oceania quiz which includes non-independent islands has been moved to Oceania islands quiz.
indicates that the link will show the location on the map.