Retention of Secretions Can Result in Full or Partial Airway

Retention of secretions can result in full or partial airway obstruction. Mucus plugging can result in which of the following?
1) Hypoxemia
2) Atelectasis
3) Shunting

A) 1, 2, and 3
B) 1 and 2 only
C) 1 and 3 only
D) 2 and 3 only