The correct answer is B: Ottawa. Ottawa is the capital city of Canada. Located in eastern Ontario, it sits on the Ottawa River and is home to the Parliament of Canada, as well as numerous federal government departments and agencies. Its selection as the capital was a strategic decision in the mid-19th century to provide a compromise between the rival claims of larger cities and to locate the capital closer to the geographical center of the then-United Canada.
Option A: Toronto is incorrect. Toronto is the largest city in Canada and the provincial capital of Ontario. It is a major economic, cultural, and financial hub, but it is not the national capital.
Option C: Quebec is incorrect. While it is a historically significant city and the provincial capital of Quebec, it is not the capital of the entire country. Quebec City is known for its strong French-Canadian culture and historic architecture.
Option D: Vancouver is incorrect. Vancouver is a major city located on the west coast of British Columbia, known for its port, natural beauty, and as a gateway to Asia. It is a significant economic and cultural center but does not hold the status of Canada's national capital.