致病力最强的脑膜炎双球菌为（）
A.A群
B.B群
C.C群
D.Y群
E.W-135群
参考答案：C
Lots of medicine as well as equipment such as tents _______ offered to the area since the earthquake occurred.
A．has been
B．have been
C．is being
D．are being
专卖
