Official transcripts和academic credentials认证的问题

打算申的项目有以下的要求：

Official transcripts from all previous colleges/universities attended.
All official transcripts MUST be submitted in the native language and accompanied by a certified English translation. The translator MUST be certified by one of the following:
;Institute for International Education (IIE)
;Amideast
;Saudi Arabian Education Mission
;United States embassy or consulate

Your international academic credentials MUST also be evaluated by one of the following agencies. You will be responsible for arranging the evaluation of your international academic credentials and having the evaluation sent to the Admissions Office.
Agencies/Agency Report Required

American Association of Collegiate Registrars and Admission Officers (AACRAO)/Basic Statement of Comparability
Academic Credentials Evaluation Institute, Inc. (ACEI) /Basic Report
World Education Services, Inc. (WES) /Document-by-Document Report
International Education Research Foundation (IERF) /General Report

请问一下，这要求认证的是官方成绩单和在读证明？怎么成绩单还要翻译机构翻译...我学校有官方翻译的可以么？