Lung volumes or capacity which cannot be measured by simple spirometry

 # Which of the following lung volumes or capacities cannot be measured by simple spirometry?

 A. Vital Capacity (VC)

B. Functional Residual Capacity (FRC)

C. Inspiratory Capacity (IC)

D. Expiratory Reserve Volume (ERV)

B. Functional Residual Capacity (FRC)

Explanation: Simple spirometry measures lung volumes and capacities that involve active breathing, such as Vital Capacity (VC), Inspiratory Capacity (IC), and Expiratory Reserve Volume (ERV). However, Functional Residual Capacity (FRC), which is the volume of air remaining in the lungs after a normal exhalation, cannot be measured directly by simple spirometry because it includes residual volume (RV), which requires specialized techniques like helium dilution, nitrogen washout, or body plethysmography to assess.