A dry rolling-seal spirometer is checked by injecting 3-L volumes at different flows (high,medium,and low)with the following results: Which of the following explains these data?

A) An improperly functioning bacteria filter is in the circuit.
B) The rolling-seal is sticking or leaking.
C) The spirometer has not been calibrated.
D) The 3-L volume is being corrected to BTPS.