假设conn为数据库连接对象，下面哪条语句可向表TeacherInfo中添加变长字符串类型的Name列

A、seq="INSERT INTO TABLE TeacherInfo ADD Name VARCHAR(50)"conn.execute(seq);

B、seq="ALTER TABLE TeacherInfo ADD Name VARCHAR(50)"conn.execute(seq);

C、seq="ALTER TABLE TeacherInfo ADD Name VARCHAR(50)"conn.commit(seq);

D、seq="INSERT INTO TABLE TeacherInfo ADD Name VARCHAR(50)"conn.commit(seq)