During Cardiac Auscultation, the Nurse Hears a Sound Immediately Occurring

During cardiac auscultation, the nurse hears a sound immediately occurring after the S₂ at the second left intercostal space. What should the nurse do to further assess this sound?

A) Ask the patient to hold his or her breath while the nurse listens again.
B) No further assessment is needed because the nurse knows this sound is an S₃.
C) Watch the patient's respirations while listening for the effect on the sound.
D) Have the patient turn to the left side while the nurse listens with the bell of the stethoscope.