What distinguishes a graduate degree from an undergraduate degree?

A graduate degree is distinguished from an undergraduate degree primarily by the fact that it is earned after the completion of an undergraduate degree. This reflects a progression in education where graduate programs build upon the foundational knowledge and skills gained during undergraduate studies. To pursue a graduate degree, students typically need to have completed a bachelor's degree or its equivalent, which demonstrates that they possess the necessary background.

In contrast, the other choices do not accurately capture the distinction. Graduate degrees do require prior education, making the second option incorrect. While some undergraduate programs can be vocational, many are also academic and lead to a wide range of fields, so the third option does not hold true. Finally, while some graduate degrees are doctoral, many are master's degrees, which means the description in the fourth option is overly restrictive and not applicable to all graduate programs.