Can two family and multifamily dwellings have one set of service entrance conductors for common areas?

In the context of electrical installations for two-family and multifamily dwellings, it is permissible to have one set of service entrance conductors serving the common areas of the building, which is why the answer is correct. This arrangement is often seen in multifamily units where the common areas may include hallways, laundry rooms, and other shared facilities.

Service entrance conductors are designed to handle the electricity required for multiple dwelling units, and when implemented correctly, they provide an efficient means of delivering power to both private living spaces and shared amenities. The National Electrical Code allows for this setup to minimize the complexity of electrical installations, as each unit can still receive its individual meter while benefiting from shared service infrastructure.

The other options imply restrictions or conditions that are not necessary under the NEC guidelines. For example, stating that only public areas can use a single service entrance could undermine the practical applications of shared utility within private residence contexts. Similarly, suggesting that additional circuits are needed may complicate what is allowed under current standards and best practices. Therefore, the ability to utilize a single set of service conductors is both allowed and practical in these dwelling types.