Which of the following is the minimum lot frontage for an economic single-detached house on an irregular lot?

The minimum lot frontage for an economic single-detached house on an irregular lot can be determined based on zoning bylaws and regulations that often dictate what is permissible in residential areas. In many jurisdictions, a minimum lot frontage of 4 meters is considered adequate for economic housing types, including single-detached homes. This measurement allows for a smaller footprint while still accommodating the necessary access to the property and ensuring compliance with safety standards, such as fire access.

In contrast, the other options typically suggest larger frontages that may apply to more standard or sophisticated lots but do not reflect the minimum requirements for economic models, particularly those on irregularly shaped parcels. This makes 4 meters the most practical and commonly accepted minimum standard for an economic single-detached house lot.