Should I only mark mexican / white? My last name is Gomez if that changes anything.
You are permitted to mark anything that fits your real situation. You are also permitted to mark nothing at all. It has been and will continue to be the law that college students are not required to self-identify with any race or ethnic group unless they want to. Next year, most college forms should follow the federal regulation that says by next year that those forms should first ask a yes or no question about Hispanic ethnicity and then a second question asking “choose one or more” from the federally defined race categories. This year most college application forms are not organized that way. What your last name is shouldn’t cause a college to guess one way or the other. Not everyone identifies with an ethnicity commonly associated with a particular name, and not all family names are associated with just one ethnicity. The Census Bureau has done much study of this, and there are people with your family name who don’t self-identify as Hispanic when asked.
*Sadly, we had to bring back ads too. Hopefully more targeted.