A.SELECT 姓名,性别,YEAR(DATE())-YEAR(出生日期)年龄 FROM 职工 WHERE年龄<=40 B.SELECT 姓名,性别, YEAR(DATE())-YEAR (出生日期) 年龄 FROM 职工 WHERE YEAR(出生日期)<=40 C.SELECT 姓名,性别, YEAR(DATE())-YEAR (出生日期) 年龄 FROM 职工 WHERE YEAR (DATE())-YEAR (出生日期)<=40 D.SELECT 姓名,性别,年龄=YEAR(DATE())-YEAR (出生日期) FROM 职工 WHERE YEAR(DATE())-YEAR(出生日期)<=40