The view ______ many scientists hold is ______ too much emission of carbon dioxide is destructive.[    ]

A. what ,that          

B. that, which    

C. that, that        

D. which, which

变压器的绕组若采用交叠式放置，为了绝缘方便，一般在靠近上下磁轭的位置安放（）。

A、低压绕组

B、高压绕组

C、中压绕组

D、补偿绕组