Not less than that of the largest draft-control device outlet or the largest flue outlet, plus 20% of the sum of the outlet areas of the additional appliances is the definition of what?

• A. The smallest draft-control device outlet.
• B. The sum of all outlet areas without adjustment.
• C. Not less than the largest outlet.
• D. Not less than that of the largest draft-control device outlet or the largest flue outlet, plus 20% of the sum of the outlet areas of the additional appliances.

Answer: (D)