I would like option A the best for a student who doesn’t change her/his mind about the major.
But, some of the students are late bloomers. They “think” they like the major, get admission in their desired major, only to change it later. The attrition rate of the particular major in the particular college will speak a lot to form an admission policy.
I like option D for some other students. Admission to the desired major for some students. If the student is not entirely sure or doesn’t have the required GPA, etc; allow them the general ed courses which will let them explore their options. The Universities should design the courses to allow a lot of flexibility to choose the major in the allied fields, e.g. if the student is not certain about Engineering (or a particular type of Engineering) or if the student wants to be an engineer but missed the necessary cut offs by just a small margin, s/he should get into such general ed courses which will allow her/him to either enter the college of Engineering or some other major in Science. Business, and the other majors will follow a similar model.
My concern is that such majors are mostly in a different colleges (Henry Samueli for engineering, Haas for business etc), and inter-college transfers are difficult. Can the Universities come up with a common pool programs for such students at least for a limited number of students? That way, many students, and parents can save a lot of money, and years if the student needs to change/choose her/his major.