What is true regarding Able's factory after a residential zoning ordinance is adopted?

When a residential zoning ordinance is adopted, existing factories or businesses that do not comply with the new zoning laws may become classified as nonconforming uses. This means that while the property is no longer consistent with the new zoning regulations, it can continue to operate as it was prior to the adoption of the ordinance. Nonconforming use allows property owners like Able to maintain their current operations without being forced to close or relocate immediately, providing they do not significantly alter the use of the property.

The rationale behind allowing nonconforming uses is to prevent the abrupt loss of businesses that existed before the change in zoning, ensuring that property rights are respected while allowing municipalities to implement new zoning rules. In many jurisdictions, there are specific conditions under which nonconforming uses can continue, such as not expanding the operation substantially or changing its nature.

In contrast, if the answer had suggested that Able must close the factory immediately, it would imply a retroactive enforcement of the new ordinance, which typically does not occur. Forcing relocation would not be applicable unless the factory was involved in causing significant public harm or nuisance, and converting the factory into residential units would require compliance with the new zoning regulations, often necessitating a rezoning process.