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: Physiology
The conducting airways are referred to as the anatomic dead space. TRUE about measurement of anatomical dead space is: 
Select and explain. 
A. 1 mL of dead space per pound of ideal body weight, B. 5 mL of dead space per pound of ideal body weight, C. 10 mL of dead space per pound of ideal body weight, D. 15 mL of dead space per pound of ideal body weight
A: 1 mL of dead space per pound of ideal body weight
Answer: A: 1 mL of dead space per pound of ideal body weight 
Explanation: For a normal, healthy subject, the anatomic dead space can be estimated by referring to a table of standard values matched to sex, age, height, and weight or body surface area. A reasonable estimate of anatomic dead space is 1 mL of dead space per pound of ideal body weight. To determine the anatomic dead space in a paicular patient, Fowler's method is used. Ref: Levitzky M.G. (2007). Chapter 3. Alveolar Ventilation. In M.G. Levitzky (Ed), Pulmonary Physiology, 7e.