The maverick heart sound

An asymptomatic 29-year-old woman presented for prenatal counselling. She had a history of a heart murmur since childhood and a previous echocardiogram suggesting 'enlargement of the heart'. Physical exam revealed normal jugular venous pressure and contour. Precordial palpation was unremarkable. Auscultation, however, was abnormal; findings on inspiration and expiration are presented in Figure 1, sound clip.

Based on the phonocardiogram and online supplementary audio clip, which of the following is correct? An early diastolic filling sound (S3) is heard, indicating increased right ventricular filling pressures.An ejection click without respiratory variation and a systolic ejection murmur are heard, consistent with bicuspid aortic valve stenosis.An ejection click with respiratory variation and a systolic ejection murmur are heard, consistent with pulmonic valve stenosis.A holosystolic murmur with inspiratory augmentation is heard, indicating tricuspid regurgitation.