Which of the following italicized parts does NOT serve as an appositive？A．Most students in

Which of the following italicized parts does NOT serve as an appositive？

A．Most students in our class, particularly David and Chris, are fond of Music.

B．He always spoke so — slowly but energetically.

C．The question whether to confess it or not troubled him.

D．There is nothing to fear.

请帮忙给出正确答案和分析，谢谢！