Read Paragraph Below and Answer the Questions That Follow It

Read paragraph below and answer the questions that follow it.
(1) There types of post-secondary institutions offer unique credentials that serve as pathways to different kinds of careers. (2) The first type of post-secondary institution is the university. (3) At universities, students first earn a bachelor's degree that prepares them for professional positions in education, medicine, engineering, and many other fields requiring four or more years of study. (4) The second type of post-secondary institution, the community college offers associate degrees. (5) Some of these degrees, which can be earned in as little as two years, prepare students to transfer to a university to continue working toward a bachelor's degree. (6) Many other associate degrees serve as the minimum credential needed to enter careers such as nursing, machining, legal assisting, and office administration. (7) A third type of post-secondary institution is the vocational-technical or career college. (8) These schools typically offer a certificate upon completion of a short-term training program (usually 18 months or less) in fields such as culinary arts, truck driving, plumbing, or hair styling.
-On what basis does the writer classify post-secondary institutions?

A) number of students enrolled and size of campus
B) age, gender, and race of student body
C) type of credential and length of study