I believe the answer is: all three - age, class, and our place in history - because those are all ways in which society guides college attendance
In almost all societies, we have age requirement before we can fill out college application. Our palce in history is strongly correlated to the type of class that can enter college. In the past, only people with strong nobility background have the right to enter college, nowdays all classess of citizens have the right to enter college.
Three campus roommates are talking about why they are in college. A sociological view of going to college highlights the effect of all three - age, class, and our place in history, because those are all ways in which society guides college attendance.
