When Assessing the Pulmonary Arterial Waveform,the Nurse Notices Dampening

When assessing the pulmonary arterial waveform,the nurse notices dampening.After tightening the stopcocks and flushing the line,the nurse decides to calibrate the transducer.What are two essential components included in calibration?

A) Obtaining a baseline blood pressure and closing the transducer to air
B) Leveling the air-fluid interface to the phlebostatic axis and opening the transducer to air
C) Having the patient lay flat and closing the transducer to air
D) Obtaining blood return on line and closing all stopcocks