-the set of people with Social Security cards and the set of Social Security numbers
Explanation:
There's literally no relation between the height of a tree and the number of trees in a forest that can be clearly seen. Same goes to models and people in a certain town. Birthdays and Students in Class definitely have no correlation as isolated pieces of information. The number of people with social security numbers and the amount of numbers in a SS Card, though, have a direct relation, since the number has to be large so the amount of people that need such a number can have unique numeric representations of their Social Security.
