根据语境，填入适当的词语或句子，补全对话。

A: Hello, Mr Zhang!

B: Hello, Bob! You look worried and nervous.  _    1      ?

A: I have a big problem. _    2      .

B: What's your problem?

A:  You know I love basketball best.  But since I am in Grade Three,  my parents don't _   3      .

B: Maybe your parents are right.  Work must come first.

A: I see. But I      4      all my lessons. And I should be allowed to play basketball.

B: If I were you, I would have a talk with parents.

A: The problem is that they don't give a      5      .

B: OK! Let me talk it with your parents.

A: Thank you! Mr Zhang.

齿轮每转一周的最大转角误差，可通过检查（）来反映。

A.齿圈径向圆跳动和公法线长度变动 

B.齿圈径向圆跳动和齿形误差 

C.基节误差和齿形误差 

D.基节误差和公法线长度变动