Faced with failure it is the most important for us to keep up good state of mind.A/ ;

问题补充：

Faced with failure, it is the most important for us to keep up good state of mind.

A/ ; a

Ba ; /

Cthe ; /

D. / ; the

答案：

(答案→)A. / ; a

B. a ; /

C. the ; /

D. / ; the

解析：“面对失败”此处“失败”是不可数名词，所以前不加冠词。a state of为固定短语，所以答案A。