Which project linked Lake Superior to the rest of the Great Lakes?

• A. Soo Locks
• B. Erie Canal
• C. Panama Canal
• D. St. Lawrence Seaway

Answer: (A)

The main idea is how ships move between bodies of water that sit at different elevations. The Soo Locks on the St. Marys River lift and lower vessels between Lake Superior and Lake Huron, letting ships pass from Lake Superior into the rest of the Great Lakes system. Without this lock system, the higher lake would be effectively cut off from the other lakes. The other options don’t provide that direct link: the Erie Canal connects to Lake Erie, the Panama Canal connects oceans, and the St. Lawrence Seaway links the Great Lakes to the Atlantic Ocean but does not itself bridge Lake Superior to the rest of the lakes.