Which of the following italicized parts is used as an object？（2011)A．What do you think has

Which of the following italicized parts is used as an object？(2011)

A．What do you think has happened to her？

B．Who do you think the visiting professor is？

C．How much do you think he earns every month？

D．How quickly would you say he would come？

请帮忙给出正确答案和分析，谢谢！