Why Are the Big Five Not the Big Twelve, the Big

Why are the Big Five not the Big Twelve, the Big Eight, or the Big Seventeen?

A) Although twenty trait dimensions have been reliably identified, it's simpler to look at a smaller set of five.
B) Five dimensions encompass all possible personality traits.
C) Clusters of related traits that reliably emerge from factor analytic studies identify five core dimensions.
D) Four traits are generally recognized, but a fifth is in dispute; it's easier to include the last for now.