Which physical feature is shared by both the U.S. and Canada?

The Rocky Mountains are a significant mountain range that extends across both the United States and Canada, making them a shared physical feature between the two countries. This mountain range is known for its stunning scenery, diverse ecosystems, and recreational opportunities.

The Rocky Mountains play an essential role in influencing the climate and hydrology of the regions they traverse, including the development of rivers and lakes that are important to both nations. They are a defining geographical feature that contributes to the natural beauty and biodiversity found in both Canada and the U.S.

The other options, while noteworthy features, do not span both countries in the same way. The Appalachian Mountains are primarily located in the eastern United States, the Great Plains extend mainly through the central United States, and the Mississippi River runs entirely within the U.S., primarily defining its eastern border.