________with what the students had done, the teacher praised them highly.  [      ]

A. Delight  

B. Delighting

C. Delighted  

D. Being delighting

根据《建筑施工碗扣式钢管脚手架安全技术规范》，构配件产品的检验，出厂文件应有使用材料质量说明、证明书及产品（）

A.说明书

B.资质证

C.上岗证

D.合格证