II 型呼吸衰竭血气诊断标准为 A. PaO 2 < 7.98 kPa(60 mmHg) , PaCO 2 >6.65 kPa(50 mmHg) prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace> B. PaO 2 <6.65 kPa(50mmHg) , PaCO 2 >7.98kPa(60mmHg) C. PaO 2 < 7.98 kPa(60 mmHg) D. P A O 2 < 7.98 kPa(60 mmHg) prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>