Why Is Pulmonary Auscultation More Difficult to Assess in an Elderly

Why is pulmonary auscultation more difficult to assess in an elderly patient?

A) Pulmonary abnormalities do not result in abnormal breath sounds in this age group.
B) Coarse breath sounds are common even over normal lung tissue.
C) Fine inspiratory crackles may indicate the presence of asthma.
D) Patients often cannot sustain deep breathing of good quality.