Which type of course provides students with additional learning opportunities beyond core subjects?

The choice that accurately describes a type of course that offers additional learning opportunities beyond core subjects is "Elective." Electives allow students to choose subjects based on their interests, enabling them to explore areas outside of the required curriculum. This can include topics such as art, music, technology, or foreign languages.

While "Optional" might seem relevant, it does not specifically denote the educational context as directly as "Elective" does. "Mandatory" refers to courses that all students must take, which is the opposite of offering a choice. "Supplemental" typically refers to additional resources or materials provided to enhance learning but does not indicate a course in itself. Therefore, "Elective" best captures the idea of courses that enhance learning opportunities beyond the essential subjects.