A nurse is collecting data about a client's cardiac functioning. The nurse auscultates an S3 sound. Which of the following causes should the nurse suspect?

A. Closing of semilunar valves: Closure of semilunar valves (aortic/pulmonic) produces the S2 sound. B. Ventricular gallop: An S3 is a ventricular gallop heard just after S2 and is associated with increased ventricular filling pressures (e.g., heart failure). C. Atrial gallop: An atrial gallop is S4, heard just before S1 and associated with a stiff ventricle. D. Closing of the atrioventricular valves: Closure of AV valves (mitral/tricuspid) produces the S1 sound.