Final answer:
The largest and busiest port in Canada is the Port of Vancouver, which serves as a key gateway for trade between the Asia-Pacific region and North America.
Step-by-step explanation:
The largest and busiest port in Canada is the Port of Vancouver. This port is not only vital for Canada's trade but also recognized internationally for its significant volume of cargo and container throughput. The Port of Vancouver handles diverse types of cargo and is strategically located on the west coast of Canada, serving as a gateway to the Asia-Pacific region and North America. While other ports in Canada, such as the Port of Montreal, Port of Halifax, and Port of Victoria, also play important roles in the country's trade and transport, none match the size and activity level of the Port of Vancouver.
It is important to note that the list provided from the National Ballast Information Clearinghouse (NBIC) report of 2014, showing the top 20 ports in terms of overseas ballast water discharged, does not include Canadian ports, as it focuses on the United States. Therefore, the Port of Vancouver is not on this list, but it is well-documented through various other sources as Canada's premier port.