Like @collegemom3717 mentioned, how is your son planning on getting any work experience in the summer? Does your child want to go into the workplace after college or into grad school and a doctoral program?
Also, does your child have any other interests besides these three majors? College is a time when you can explore different areas even though you don’t intend to major in it or do anything professionally. Maybe there’s classes on a particular part of the world, or a foreign language he always wanted to pick up, or a theater class, or just find out who the most beloved profs are and take a class with them just to get that experience. It is highly unlikely that your son will ever have the opportunity to have mini academic adventures with a group of similarly-minded peers in an array of subjects. In the future it will just be in his areas of specialization, or maybe a monthly book group, or taking a class online or at a local college while working full-time, or just studying a subject on his own, none of which, I have found, were as interesting as some of the fun electives I took.