I've been asked my profession a number of times on entering the US (as a visitor - not on a work permit). I'm an electrical engineer, but my response is usually just "engineer". Electrical engineering is such an incredibly broad profession, including everything from chip designers to radio engineers to power systems. Just how many quizzes is CBP going to have design to cover every branch of my profession and not deny an antenna designer entry because he doesn't know anything about power transformers?