What’s the difference in the competition ? Stats of those accepted ? Thanks 
Nursing is the most competitive major at SDSU with close to a 5% acceptance rate. Business Admin had around a 42% acceptance rate last year.
In general, an Eligibility index of around 4100+ SAT or 1000+ ACT will make you a competitive applicant for Business Admin. For Nursing, you are looking at a minimum EI of 4300+ SAT or 1100+ ACT for Nursing. SDSU also changed their Nursing program admission process this year and it is now only Direct admit. If you are not accepted as a Freshman, you cannot switch into the major later.