Final answer:
To correct an AP ankle projection with open medial mortise joint and closed lateral mortise joint, the radiographer can increase internal rotation.
Step-by-step explanation:
To correct an AP ankle projection where the medial mortise joint is open while the lateral mortise joint is closed, the radiographer can make the following adjustment:
B. Increase internal rotation
By increasing internal rotation of the ankle, the medial mortise joint will close, resulting in a more balanced image. This adjustment ensures proper alignment of the ankle joint and improves the diagnostic quality of the radiograph.