Which of the following statements best describe Demand Control Ventilation (DVC) in Building Automation Systems?

It satisfies indoor ventilation rates by preconditioning outdoor air with the exhaust air to decrease energy cost during cold, warm, or humid weather

It's a prescriptive procedure in which outdoor air intake rates are calculated based on the energy cost method that compares a proposed building design to a base annual energy cost design

It's a building standard for enclosed spaces in which biological, chemical, and physical contaminants are considered to meet thermal comfort requirements

It's an active evaluation of outdoor and indoor space conditions to determine the amount of thermal, mechanical and natural conditioning that is required