The nurse is assisting with a subclavian vein central line insertion when the client’s oxygen saturation rapidly drops. He complains of shortness of breath and becomes tachypneic. The nurse suspects a pneumothorax has developed. Further assessment findings supporting the presence of a pneumothorax include（）

A. diminished or absent breath sounds on the affected side.

B. paradoxical chest wall movement with respirations.

C. tracheal deviation to the unaffected side.

D. muffled or distant heart sounds.

现代城市规划体系的核心是( )。

A．规划管理体系

B．规划法规体系

C．规划行政体系

D．规划编制体系