无消毒和抑菌作用的根管充填材料为（）.
A.氢氧化钙糊剂
B.牙胶
C.碘仿糊剂
D.根管糊剂
E.酚醛树脂
参考答案：B
26. Soldiers stood next to a police truck, looking at the crime scene _______ a woman was gunned down in a poor neighborhood of the border city of Iran October 18, 2009.
A．that
B．which
C．where
D．why
