Apart from antarctica what is the least populated continent

Australia

Explanation:

Australia was once a part of the Antarctic continent, as evidence given by the earlier geologic formations. Antartica has about 25,494,900 population i.e density of 3.3/km square and an area of 7,692,024 km square.  Like the mainland, Australia is one of the sparsely populated continents in the world. Antarctica being a large continent covered with permafrost is uninhabitable and is only ground for scientific research. The landmass of Australia is mainly divided into 5 major parts, indigenous people used to roam on this continent for 65,000 years. Being the oldest flattest and driest place of inhabited continents in the world. Also, the mega biodiversity of this zone is found in the desert.

The answer for your problem would be a. 7