The nurse detects a possible extra heart sound while assessing an adult client. To verify this finding, which action should the nurse take?

A. Doppler ultrasound is used for assessing blood flow and is not necessary to verify heart sounds. B. The diaphragm is better for hearing high-pitched sounds like normal heartbeats, murmurs, and lung sounds. C. The bell of the stethoscope is best for auscultating low-pitched sounds, such as extra heart sounds like a S3 or S4, which are often related to heart failure or other cardiac conditions. D. A pulse oximeter assesses oxygen saturation, not heart sounds.