<p>As far as I know, it can be any of the above that you listed. You could even just say, very un-eloquently, "Unknown." I know a couple people who got in with that. When I applied, I wrote 2 or 3 sentences.</p>
<p>That does not really matter either, but I think they expect some correlation between your transcript and your possible majors. For example, if you go to school that offers AP Calc, but you are in Algebra II as a senior, and put Math as your possible major, I doubt you'll be taken seriously...</p>
<p>Don't try to play the system by guessing what they would want you to write. Put something you are actually interested in. (And make sure Stanford offers the major that you write down ;)...)</p>
<p>And this is already mentioned in another thread, but I want to reiterate it - don't worry that certain majors are more "desirable" than others, like you have a better chance if you put Classics than if you put Biological Sciences (which is a big major). Stanford, as far as I know, has no quotas for how many people can be in each major, and the school is very supportive of people who wish to change their major. So just be honest.</p>