有学生表,其结构为:student(学号,姓名,性别,年龄),查询所有年龄小于等于18岁的女同学、并按年龄降序排序生成新的表stud,正确的SQL命令是()
A.CREATE TABLE stud AS SELECT * FROM student WHERE 性别=女 AND 年龄<=18 ORDER BY 年龄 DESC; B.CREATE TABLE stud AS SELECT * FROM student WHERE 性别=女 AND 年龄<=18 ORDER BY 年龄 DESC; C.CREATE TABLE stud AS SELECT * FROM student WHERE 性别=女 AND 年龄<=18 ORDER BY 年龄 ASC; D.CREATE TABLE stud AS SELECT * FROM student WHERE 性别=女 AND 年龄<=18 ORDER BY 年龄;