Final answer:
Ontario and Quebec are the two provinces that produce more than three-quarters of Canadian manufactured goods due to their population, infrastructure, and strategic location.
Step-by-step explanation:
The two provinces that produce more than three-quarters of Canadian manufactured goods are Ontario and Quebec. Ontario, with the largest population, and Quebec, the predominantly French-speaking province, have been central to Canada's manufacturing sector since the industrialization of the 19th century. These provinces have the necessary infrastructure, skilled labor, and are strategically located with access to the Great Lakes and the St. Lawrence River, which facilitates trade and transportation.