Final answer:
The Canadian Shield is a wilderness area due to its poor soil, harsh climate, and remoteness, making it less suitable for agriculture and more challenging for permanent human settlement.
Step-by-step explanation:
The Canadian Shield region is known as a wilderness because it is a vast area of ancient pre-Cambrian rocks covered by a thin layer of soil. Its landscape is characterized by exposed bedrock and boreal forests, with the area being rich in minerals and timber. However, its soil is relatively poor, and the climate is harsh, which makes it less suitable for agriculture and more difficult to inhabit compared to other regions. Its remoteness from major population centers and the overall harsh living conditions contribute to its designation as a wilderness area.