Chinese by the largest number of people.A. is speakingB. speak C. speaksD. is spoken

问题补充：

Chinese by the largest number of people.

A. is speaking

B. speak

C. speaks

D. is spoken

答案：

A. is speaking

B. speak

C. speaks

D. is spoken

解析：句意:说汉语的人数最多。这里的主语是Chinese，意思是汉语，根据句意可知，主语Chinese 与动词speak 构成被动的关系，应该用被动语态。故选D。A选项是现在进行时；B是一般现在时，复数形式；Ｃ选项是一般现在时的第三人称单数形式。