The work breakdown structure(WBS) used in the classical sense is a practical methodology used for ______.

A) adding activities to the project
B) expanding the scope of the project
C) developing a responsibility matrix for work assignments
D) delineating project work effort into discrete and logical sub-elements

取“员工年龄情况表”的“年龄”列和“所占比例”列的单元格内容(不包括“总计”行)，建立“分离型圆环图”，系列产生在“列”，数据标志为“百分比”，图表标题为“员工年龄情况图”，插入到表的A9:C19单元格区域内。