What responsibility does the tenant have regarding common exhaust ducts?

The correct choice highlights the tenant's specific responsibility regarding the common exhaust ducts related to their operation. In the context of NFPA standards, the tenant is tasked with the protection of ducts that serve their particular cooking hoods up to a specified connection point. This ensures that the tenant maintains the cleanliness and functionality of the duct system that directly affects their operation, ultimately contributing to overall fire safety and efficient ventilation.

By focusing on protecting the ducts that serve their hoods, tenants are fulfilling an essential role in preventing any buildup of grease or other combustible materials that could pose a fire hazard. This responsibility is integral to maintaining operational safety and compliance with fire safety regulations. Other choices might imply broader responsibilities that are typically not part of a tenant's obligations, such as the full maintenance of common duct systems or the obligation to install completely new exhaust systems, which generally fall under the jurisdiction of the property owner or designated maintenance personnel.