A client has a pulmonary embolism and is started on oxygen. The student nurse asks why the client's oxygen saturation has not significantly improved. What response by the nurse is best?

“The client needs immediate intubation and mechanical ventilation."

"Maybe the client has respiratory distress syndrome."

"The client is breathing too slowly and it interferes with oxygenation."

"The blood clot interferes with perfusion in the lungs."