The correct answer is B) A terminal reheat system. This is the correct answer because the illustrated diagram depicts a central air handling unit that supplies air to multiple terminal reheat units, which is the defining characteristic of a terminal reheat HVAC system. In this system, the central unit conditions the air to a uniform temperature, and the terminal reheat units then adjust the air temperature as needed for each individual zone. The other answer choices are incorrect because they do not accurately describe the system shown in the illustration. A single zone system has only one thermostatically controlled zone, a dual duct system has separate hot and cold air ducts, and a variable air volume system adjusts the airflow rather than the temperature at the terminal units.