When recruiting new staff, Business Studies would generally be preferable over computing- the reason being that the principles of business don't change over time, knowledge about understanding how the economy works is always useful to a business, and computing skills are often learnt "along the way" in any case. If a company thinks that its' staff need further training it is much easier and more effective for them to send them on a bespoke computer training course rather than have them begin to learn all about how business in general works. She would be making a great choice by going for business studies. Computing would be a useful add-on subject if she could do both, but 3 years to learn computing alone would not be time well spent, in my opinion. If she is able to work during her education, I would strongly encourage it- the best place to learn about business is in the workplace.