What geographical feature is a key resource shared by Canada and the United States?

The Rocky Mountains are a significant geographical feature that stretches across Canada and the United States, making them an essential shared resource. This mountain range not only serves as a natural border between the two countries but also plays a vital role in ecosystem diversity, wildlife habitat, and water resources. The Rockies impact climate and weather patterns on either side, and their presence influences various industries, including tourism, logging, and mining.

In addition to being a source of natural beauty, the Rocky Mountains are vital for water systems that contribute to rivers and lakes, supporting communities on both sides of the border. This interconnectedness highlights how such geographical features can foster cooperation and resource management between Canada and the United States.

The other options are geographical features, but they do not extend through both countries or do not serve as significant shared resources in the same way the Rocky Mountains do. For example, the Missouri River is a major river in the United States but does not flow through Canada, the Andes are located in South America, and while the Ohio River is important in the United States, it does not have any relevance to Canada.