Explanation:

- Urban geography: Studies the spatial distribution of human populations in urban areas, city functions, and location. It's broader and focuses on how cities grow, interact, and are distributed.

- Urban morphology: Examines the physical form, structure, and layout of urban areas—such as street patterns, building shapes, and land use. It mainly deals with physical appearance.

- Urban ecology: Studies the relationships between people and their urban environments, analyzing how social groups and physical surroundings influence one another. It looks at patterns of growth and spatial distribution of groups.

- Urban topology: Refers more specifically to the spatial relationships regardless of strict dimensions—how places are connected in a network sense, not used commonly for urban community growth or complexion study.

Correct Answer:

Option:3, Urban ecology