.— Are you satisfied with the result of the examination?

— Not at all. _______.

A．That’s all right

B．It’s up to you

C．It couldn’t be worse

D．It depends

7075铝合金是一种什么铝合金（）？

A、AL－Mg合金

B、AL－Zn合金

C、AL－Cu合金

D、AL－Si合金