Final answer:
The importance of the service sector in the Canadian urban system increased during the Post-Industrial Phase.
Step-by-step explanation:
In the Canadian urban system, there was an increase in the importance of the service sector during the Post-Industrial Phase. This phase is characterized by a shift from a manufacturing-based economy to a service- and information-based economy. The service sector now employs about three-quarters of all Canadians and generates over 60 percent of the GDP, making it the most prominent sector in the Canadian economy.