Which lung sounds are expected?

A. Bronchovesicular sounds are normal lung sounds that are typically heard over the mainstem bronchi and are expected during auscultation. B. Bronchial sounds are also normal and are typically heard over the trachea; they are expected lung sounds. C. Dullness is not a lung sound but rather a descriptor of percussion notes, typically indicating fluid or solid mass in the lungs. D. Flatness is also not a normal lung sound but refers to a percussion note that can suggest the presence of fluid or a solid mass.