Your Patient Is Suspected of Having One or More Pulmonary

Your patient is suspected of having one or more pulmonary emboli. He is tested by inhaling a radioactive gas and receiving an intravenous injection of radiolabeled particles. Which test results on his ventilation-perfusion lung scans will prove he has a pulmonary embolism?
1) Normal blood flow through the lungs
2) Decreased blood flow through the lungs
3) Normal ventilation through the lungs
4) Decreased ventilation through the lungs

A) 2
B) 4
C) 2, 3
D) 1, 4