The nurse is caring for a client being evaluated for peritonitis due to suspected gastric ulcer perforation. Which of the following findings on an abdominal x-ray supports this diagnosis?
A. Calcification in the left upper quadrant (LUQ)
B. The presence of free air in the abdominal cavity (Act I)
C. Calcified stones in the right upper quadrant (RUQ)
D. Shadowing at the junction of the kidney and the ureter (Act II)