Final answer:
Toronto experienced the highest growth rate of 'built-up' areas between 1971 and 2011, influenced by immigration, economic expansion, and its prime location in Ontario, known as South Canada.
Step-by-step explanation:
Between the years 1971 and 2011, the city with the highest growth rate of 'built-up' areas among the options given is Toronto. Toronto's growth has been influenced by a variety of factors over the years, such as immigration, urbanization, and economic expansion. This growth has included both population and physical built-up areas as the city has adapted to accommodate more residents and businesses.
Although specific statistics for each city during the years in question are not provided here, it is well-documented that Toronto, being in Ontario which is often referred to as South Canada, has experienced significant growth, especially due to its southern location which has made it a prime destination for immigrants and a center of commerce and industry.