Getting back to the original question....I think you should mark other and write in Berber if they give a blank....just to be on the safe side. If you did mark African American, I would be sure to clarify somewhere your situation. I doubt that labeling yourself as African American would come back to bite you in the ass later and I don't think there is anything ethically wrong with it. However, do you really want to worry about it for the next 3 1/2 years of your life?
I'll say it one more time, since it seems that many of you still haven't got the point: on every application I've seen, the box says "African-America/Black." The two terms, for the purposes of the application, are synonyms, so if you are not phenotypically black (although your ancestors may very well be from Africa), you should not check the box. It's as simple as that.
No (s)he should not check it. African American refers to people who are racially African (ie Black). You are not African American if you are a white person who grew up in South Africa. You are not African American if you are an Indian person who grew up in Kenya. In order to check that box, you must be Black.As for leg ups for Arabs, the OP's post stated that (s)he looked white. Obviously the OP isn't getting crap for being Arab if people think that (s)he is Western European. Nice try.