选C啊,因为：
I hear Mr Li is going to speak at the school meeting.--Do you know what he is going to say?
speak讲语言 speak to sb about sth
tell告诉 tell sb sth/tell sth to sb
say说 say sth to sb
talk交谈,聊天 talk to sb/talk sb about sth
say ,speak talk 和tell辨析.
▲ say一般作及物动词用,着重说话的内容,它的宾语可以是名词,代
词或宾语从句.
eg: He can say his name. 他会说他的名字.
Please say it in English. 请用英语用.
She`s saying ,Don`t draw on the wall.她在说“别在墙上画”.
▲ speak强调说的动作,不强调所说的内容 .作及物动词时,常以某种
语言作宾语.作不及物动词时,常见的搭配形式有：
speak of something/somebody谈到某事（某人）speak to sb 跟某
人讲话,此外speak还可用于在较为正式的场合了表演讲或演说.
Can you speak Japanese? 你会说日语吗?
She is speaking to her teacher. 她正在跟她的老师说话.
He spoke at the meeting yesterday. 他昨天在会上讲了话.
▲ talk 一般为不及物动词,意思是“交谈,谈话,着重强调两具之间的
相互说话.
eg: She is talking with Lucy in English.
她正在和露茜用英语交谈.
What are you talking about? 你们在谈论什么?
The teacher is talking to him. 老师正在和他谈话.
▲ tell常作及物动词,意为“讲述,告诉,动词常跟双宾语.
tell sb sth＝tell sth to sb告诉某人某事.
eg: He is telling the children a story.
他正在给孩子们讲一个故事.
Did you tell her the news?＝Did you tell the news to her?
你把这个消息告诉她了吗?