A 37-year-old truck driver is seen with a history of recent onset of shoness of breath aggravated by bending over, lying down, and exeion. On physical exam, vital signs are normal. Lung exam shows decreased air movement at the left base with an area of dullness posteriorly. Abdomen is soft without palpable organomegaly. CXR is shown.The above diagnosis can best be confirmed by
Sniff test Ultrasound of abdomen Bronchoscopy Pulmonary function test