The big fire in Shanghai, believed to ________ due to the burning of construction materials, caused

58 deaths and destroyed all the belongings of the people there.[ ]

A. have occurred 

B. occur

C. have been occurring  

D. be occurring

下列哪项为大叶性肺炎最常见的致病菌

A．绿色链球菌

B．流感嗜血杆菌

C．肺炎链球菌

D．大肠杆菌

E．绿脓杆菌