What’s the difference between the Guan wares and the Ge wares?（）

A.No difference

B.The Guan wares are much darker than the Ge wares

C.The Ge glaze is full of minute bubbles while on the Guan wares all the bubbles seem to have burst either without trace or leaving behind them a faintly pitted surface

D.There are iron lines on the Guan wares, but elaborate cobalt-blue(钴蓝) decorations on the Ge wares

正确答案：C