Lee Has Earned an Undergraduate Degree in Biology

Lee has earned an undergraduate degree in biology. He is motivated to become a doctor. He has ascertained three letters of recommendation from his professors and has applied to medical school. He has not yet proposed to his girlfriend. Which of these characteristics referring to Lee is a continuous variable?

A) his college degree
B) his school application
C) his letters of support
D) his motivation
E) his status as a fiancée