Apply as Undeclared vs a major?

My son will be applying to Rutgers NB. It is his first choice. He has a 3.255 unweighted GPA. 1220 SAT. Despite three sports concussions, he has performed very well in school. Strong extra curr. activities and volunteer work. He would like to attend the business school but his stats may not be enough. SAS Economics major or SEBS Environ. & Business Econ. are also possibilities. My question is, would it be best to apply as undeclared or declare a major for SAS and SEBS?
Appreciate any thoughts or guidance.