Why is Greenland usually classified as part of North America despite its political connection to Denmark?

Greenland is classified as part of North America primarily due to its physical geography and geological structure, which distinguish it from its political association with the Kingdom of Denmark.12

Geographically, Greenland is physically connected to the North American continent by a submarine ridge that is no deeper than 600 feet (180 meters). Structurally, the island is considered an extension of the Canadian Shield, a stable platform of ancient Precambrian rock that forms the core of the North American continent. Furthermore, Greenland is located in close proximity to the Canadian Arctic, separated from Ellesmere Island by only 16 miles (26 km).32

While Greenland maintains a political connection to Denmark—functioning as a self-governing overseas administrative division that manages its own domestic affairs while Denmark oversees defense and foreign relations—its physical and geological ties firmly align it with the North American landmass.12