He ＿＿＿articles for our wall-newspaper these three years, and he ＿＿＿about forty articles.

A．has been writing； has written

B．has been writing； wrote

C．is writing； has been writing

D．has written； has written

急性心肌梗死合并心源性休克的主要表现为（）

A.血压不变，中心静脉压下降

B.血压下降，四肢干燥、温度低

C.双下肢水肿，颈静脉怒张

D.血压下降，肺毛细血管楔压上升

E.血压下降，心率增快