Which heart sounds are typically audible during auscultation?

The correct choice encompasses the four primary heart sounds: S1, S2, S3, and S4. During the process of auscultation, heart sounds are generated by the closure of the heart valves and are essential in evaluating cardiac function.

The first heart sound (S1) is produced by the closure of the atrioventricular valves (the mitral and tricuspid valves) at the beginning of ventricular contraction. The second heart sound (S2) occurs with the closure of the semilunar valves (the aortic and pulmonary valves) at the end of ventricular contraction.

S3, often referred to as a “ventricular gallop,” can be normal in some individuals, particularly young people or pregnant women, as it may indicate rapid ventricular filling. S4, or an “atrial gallop,” typically indicates increased resistance to filling due to the stiffening of the ventricles, which can be associated with various cardiac conditions, especially as one ages.

Thus, during a complete assessment, being able to identify all four heart sounds allows for a thorough understanding of the heart's performance and potential abnormalities, making this option the most comprehensive choice regarding what is typically heard during auscultation.