52AG makes a good point. Your student would likely have to apply to business programs in their respective business colleges, and then double major or minor with econ in the liberal arts college.
A couple things to watch out for… First, many schools do not have direct admission into their business programs. Students have to apply for general admission, and only after earning a given GPA in a set of prereq classes are they admitted into the B school. Second, many B schools do not guarantee admission into a given concentration. My nephew went to Penn State’s B school and during freshman orientation the dean explained that everyone wants finance and they only have so many seats, so the top XX students by GPA get their first choice.