What describes the spread of urban development into the countryside?

The correct choice is urban sprawl, which refers to the uncontrolled expansion of urban areas into the surrounding rural land. This phenomenon typically occurs as cities grow and populations increase, leading to the development of residential, commercial, and industrial areas in regions that were previously rural or undeveloped. Urban sprawl is characterized by low-density housing, reliance on automobiles, and a tendency to create separate zones for different land uses, which can lead to various environmental and social challenges.

Urban infill focuses on filling vacant or underused parcels of land within existing urban areas, enhancing the density without expanding outward. Rural development refers to initiatives aimed at improving the economic and social conditions of rural areas, while urban regeneration involves revitalizing and renewing old or declining urban areas, improving infrastructure and amenities rather than spreading outward into the countryside.