题目内容：
根据以下材料，回答题Tom was aged four but he was talkinglike a two-year-old baby. He was saying such things as"kick ball" and"want car", and using lots of one-word sentences. He should have beensaying some really long sentences and telling stories with them. He wasn't.Something had gone terribly wrong.
Quite a few children have what is called a"language delay". For some reason they don't learn to speak asquickly as they should. Their friends shoot ahead and they're left behind. As aresult, they get very lonely. Nobody wants to talk to you if you can't talkback.
Can anything be done to help thesechildren? Yes. They can go to see a speech therapist--a person who's speciallytrained to work out what's wrong and who knows how to teach language tochildren. This is what happened to Tom. The speech therapist played some gameswith him and heard how he talked.She made a recording of his speech,and chatted to his morn and dad about his background. They'd taken Tomto see a doctor, but the doctor hadn't found anything wrong with him.
He seemed perfectly normal in everyway--except he just wasn't talking.
After Tom and his parents had gone home,the therapist listened carefully to the recording she'd made. Then she lookedat a chart which showed how language developed in children aged two, three,andfour. She could see Tom was a long way behind.
The next step, she decided, was to teachTom how to say some new sentences like "kick a red ball, " and"the clown is kicking a ball. " Tom didn't get the new sentencesright straight away. But the therapist was very patient, and after a few morevisits he started to make some progress.
How did the author introduce thetopic of this passage ? A．By describing grammar errors made bykids.
A．By describing grammar errors made by kids.
B．By sharing experiences of speechtherapists.
B．By sharing experiences of speech therapists.
C．By using Tom, s case as an example.
C．By using Tom, s case as an example.
D．By stating his personal views toreaders.
D．By stating his personal views to readers.
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