Conditions that can affect airway patency and cause abnormal clearance of secretions include which of the following? 1. Foreign bodies 2. Tumors 3. Inflammation 4. Bronchospasm

a. 1, 2, and 3 only
b. 2 and 4 only
c. 2, 3, and 4 only
d. 1, 2, 3, and 4

ANS: D
Examples include foreign bodies, tumors, and congenital or acquired thoracic anomalies such as kyphoscoliosis. Internal obstruction also can occur with mucus hypersecretion, inflammatory changes, or bronchospasm, further narrowing the lumen.