阅读下列短文，从毎题所给的四个选项（A、 B、 C和D）中，选出最佳选项，并在答卡上将该项凃黑。
Young people can have problems with their minds. Some students become worried because they have to study very hard. Others have trouble getting on well with people like their parents and classmates.
LiWen，a junior 2 student from No.2 Middle School，could not understand his teacher and was doing badly in his lessons. He became so worried about it that he started to cut his finger with a knife.
Another student,16yearold Yang Fang from No.1 Middle School，was afraid of exams. She got very worried in one，and when she looked at the exam paper，she couldn't think of anything to write.
A recent report from JieFang Daily says about 18% of Shanghai teenagers have mental problems. Their troubles include being worried and very unhappy，and having problems in learning and getting on with people. Many students who have problems won't go for advice or help. Some think they will look stupid if they go to see a doctor. Others don't want to talk about their secrets.
Liang Yuezhu，an expert on teenagers from Beijing AnDing Hospital has the following advice for teenagers：
·Talk to your parents or teachers often.
·Take part in group activities and play sports.
·Go to see a doctor if you feel unhappy or unwell.
1．The students who often become worried or have trouble getting on with others may have________.A．no parents B．a headache