Practice question

Answer: B) Blood pH due to CO2. For Lung Volumes, Capacities and Regulation, once you lock onto the key mechanism or definition, Blood pH due to CO2 is the clear fit. If you restate the concept in your own words, the functional job described in the stem is exactly what Blood pH due to CO2 does in Lung Volumes, Capacities and Regulation. So Blood pH due to CO2 is the clean, accurate selection. If a similar stem appears later, start from the same core fact and you will land on the same kind of answer. In class notes, highlight this same phrase next to the related diagram so the wording and the picture reinforce each other.