Final answer:
The Canadian Shield is the rocky flat region that encircles Hudson Bay, is vital for its natural resources.
Step-by-step explanation:
The Canadian Shield is the correct answer to the student's question. This vast geological shield, also known as the Laurentian Plateau, is a rocky flat region that encircles Hudson Bay. Covering nearly two million square miles, it represents the ancient geological core of the North American continent. Characterized by its rocky outcrops and rich mineral deposits, it provides important natural resources such as minerals and timber, significantly contributing to the Canadian economy.