13. 依 ISBP 規定有關單據簽字，下列敘述何者錯誤？ (A)空運提單〝handling information〞框位均需填註資料並簽字 (B)單據副本無須簽署或加註日期 (C)空運提單上「託運人或其代理人之簽字」之空格均無須簽字 (D)若單據表明〝This document is not valid unless countersigned (or signed) by (name of the person or entity)〞則應簽字