Which river is connected to the history of fur trading in Alaska?

The Yukon River is deeply intertwined with the history of fur trading in Alaska due to its significance as a major transportation route for traders and trappers. During the 19th century, the Yukon River facilitated the movement of goods and furs between the interior of Alaska and trading posts along its banks. The river enabled fur traders to reach remote areas where they could acquire pelts from Indigenous peoples and trappers, which were highly valued in markets. The extensive system of tributaries and the river's length allowed for efficient access to a rich resource base, making it fundamental to the fur trade during that era.

In contrast, while the other choices also hold importance in Alaska's geography and history, they are not as directly associated with the iconic fur trading routes and the economic activities surrounding them. The Seward River, Cook Inlet, and Susitna River do play roles in the state's natural history and ecosystems, but they lack the prominent fur trading legacy that characterizes the Yukon River.