_____ is our belief that improvements in health care will lead to a stronger, more prosperous economy. [ ]

A. As

B. That

C. This

D. It

丹毒的致病菌是

A．金黄色葡萄球菌
B．溶血性链球菌
C．革兰阳性杆菌
D．厌氧性芽胞杆菌
E．革兰阴性杆菌