It was announced that only when the fire was under control          to return to their homes.

A．the residents would be permitted

B．had the residents been permitted

C．would the residents be permitted

D．the residents had been permitted

肾癌是（）

A.点状钙化

B.点片状甚至全肾钙化

C.弧线状钙化

D.珊瑚状高密度影