What type of land use pattern allows subdivisions with smaller lot lines and no setback requirements while maintaining density ratios?

The correct choice is Planned Unit Developments, which are designed to provide more flexibility in land use compared to traditional zoning regulations. In a Planned Unit Development (PUD), developers can create subdivisions that feature smaller lot sizes and reduced or no setback requirements, allowing for a more efficient use of land. This approach enables the creation of higher-density communities while still adhering to overall density ratios.

PUDs often incorporate a mix of residential, commercial, and recreational spaces, fostering a sense of community and promoting walkability. This land use pattern is particularly beneficial in urban areas where maximizing space is essential.

In contrast, downzoning generally involves changing the zoning classification to allow for less intensive land use, which would not support smaller lot sizes or increased density. Horizontal property divisions pertain to the division of land for purposes like condominiums and don't necessarily focus on density ratios, while spot zoning refers to the practice of changing the zoning for a specific parcel of land, typically to allow for different uses than surrounding properties, but it does not inherently support the features that PUDs provide such as smaller lots and reduced setbacks.