Final answer:
The length of Canada's coastline is 125,594 miles, which is obtained by adding the length of the United States' coastline (12,383 miles) to the additional length of Canada's coastline (113,211 miles).
Step-by-step explanation:
The question asks us to calculate the length of Canada's coastline based on the fact that it is 113,211 miles longer than the United States' coastline. We are given the length of the United States' coastline, which is 12,383 miles. To find the length of Canada's coastline, we simply add these two numbers together.
12,383 miles (length of United States' coastline) + 113,211 miles (additional length of Canada's coastline) = 125,594 miles.
Therefore, the length of Canada's coastline is 125,594 miles, making option A the correct answer.