A 55-year-old obese woman presents to the emergency department with acute onset dyspnea, pleuritic chest pain, and a cough. She recently underwent knee surgery. Her oxygen saturation is 92% on room air, and her heart rate is 105 bpm. Which diagnostic test is most appropriate to confirm the suspected diagnosis?
✓ Correct Answer: Option D
Given the patient's high clinical suspicion for pulmonary embolism (post-surgery, dyspnea, pleuritic chest pain, hypoxia, tachycardia), CT pulmonary angiography (CTPA) is the most appropriate and definitive diagnostic test in a stable patient.