First impressions are the most lasting. After all, you never get _____ second chance to make _____ first

impression. [ ]

A. a; the

B. the; the

C. a; a

D. the; a

“禁止攀登，高压危险!”的标志牌应制作为（）。

A、红底白字

B、白底红字

C、白底红边黑字