从下列各组句子中选出表达正确的一个句子

( )1. A. This are my sister.    

           B. This is my sisters.    

           C. This is my sister.    

           D. These is my sister

( )2. A. This isn’t me cousin.  

           B. This is me cousin.    

           C. This aren’t my cousin.    

           D. This isn’t my cousin

( )3. A. They is my brothers.    

           B. They are my brother.    

           C. They are my brothers.    

           D. These is my brothers

( )4. A. These is my mother.    

           B. This is my mother.     

           C. This is me mother.    

           D. This are my mother

( )5. A. Are this your grandmother?    

           B. Is these your grandmother?    

           C. Is these your grandfather?    

           D. Is this your grandfather?

通过采取技术和管理手段使事故发生后不造成严重后果或使后果尽可能减小，这是( )。

A．事故预防

B．事故控制

C．安全管理

D．事故对策