This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
The mechanical system in which fresh air is blown into the room by centrifugal fans so as to create positive pressure and displace the vitiated air is termed as 
Select and explain. 
A. Balanced ventilation, B. Plenum ventilation, C. Exhaust ventilation, D. Air conditioning
B: Plenum ventilation
Answer: B: Plenum ventilation 
Explanation: None