---- I’m going to Sanya for the summer holiday.

--         !                                           

A．Have a good time

B．Well done

C．Best wishes to you

D．Thanks a lot

5mm厚奥氏体不锈钢板角接焊缝可选择（）探伤方法。

A.磁粉

B.渗透

C.射线

D.超声波