《钢铁是怎样炼成的》体现了怎样的主题思想？

A. 按照合同约定完成承揽工作
B. 材料检验
C. 交付符合质量要求的工作成果
D. 依法赔偿损失

A. had they found
B. should they find
C. could they find
D. did they find

A. down to
B. up to
C. behind
D. about