Ice and snow are creating a fairytale scene in Harbin, the "Ice City",               the 27th International Ice and Snow Festival, has just opened to the public. [ ]

A. which     

B. about which   

C. where     

D. that

电泳后的湿涂膜表面未冲洗干净，从电泳槽中带出的槽液使涂膜产生再溶解，会产生针孔。( )