The correct answer is D.
Elective requirements are courses taken outside of a major and beyond the general education requirements.
Courses or subjects can be core courses or elective courses. Core courses are those that you are required to complete, in other words, they are compulsory and strongly associated with your chosen major.
Elective courses are courses the students choose from an area of study that they like or that interest them most. They are not compulsory. An elective course is chosen per the interest and passion of the student for one particular subject. These courses are not designated as part of a degree requirement. The goal of an elective course is to learn more about a subject you like and are interested in.