Which of the following sentences is INCORRECT？A．His sister rather than his parents is at h

Which of the following sentences is INCORRECT？

A．His sister rather than his parents is at home now.

B．Every boy and every girl are excited to hear the news.

C．His thanks were really sincere.

D．Either Jack or John knows the truth.

请帮忙给出正确答案和分析，谢谢！