Answer:
very complex and difficult when continents are studied as a whole
Explanation:
The definition of the term continent is not a consensus among geographers. At least three versions can be considered. The first and most used one considers that there are six continents on the planet - extensive landmasses surrounded by oceans and that shelter several countries. The second considers the existence of only five continents - now considering Antarctica as a non-continent, now considering Europe and Asia as a single continent, Eurasia, because they are located on the same tectonic plate. The third increases the number of continents to eight, considering the subdivisions of the American continent (North, Central and South) as autonomous continents.
