Final answer:
Condominiums relative to detached housing are typically more expensive in Downtown Toronto due to high demand and limited space. Gentrification in urban areas can lead to displacement of less affluent residents, increased crowding, and traffic issues. Zone B in the concentric zone model represents formerly wealthy homes converted into cheaper apartments.
Step-by-step explanation:
The cost of condominiums relative to detached housing in the Greater Toronto Area (GTA) varies depending on location. In the options provided, option a, Downtown Toronto, is typically where condominiums are much more expensive compared to detached houses, because it is the city's central business district, and housing demand there is very high with limited space for development. Areas like Scarborough, North York, and Brampton generally have lower prices for condominiums relative to downtown.
Gentrification is a related topic as it often affects housing prices. Gentrification can cause less affluent residents to be pushed into less desirable areas, making the neighbourhoods more crowded, and often exacerbating traffic issues and pollution. As for the concentric zone model, Zone B is often characterized by formerly wealthy homes that have been split into cheaper apartments, which is an outcome of changes in urban structures over time, including gentrification.