A nurse is caring for a client who has left lower-lobe atelectasis. In which of the following positions should the nurse place the client for postural drainage?

The correct answer is C: Side-lying with the right side of the chest elevated. This position allows gravity to help drain secretions from the left lower lobe, promoting lung expansion. Placing the client in a side-lying position with the right side elevated facilitates drainage and prevents pooling of secretions. Option A (Prone with pillows under the lower extremities) would not effectively target the left lower lobe. Option B (Supine in low-Fowler's position) may not provide adequate drainage for the specific lobe affected. Option D (Right lateral in Trendelenburg position) is incorrect as Trendelenburg position is not recommended for postural drainage due to increased risk of complications.