Which of the Ideas Below Is Central to the Davis

Which of the ideas below is central to the Davis and Moore theory of stratification?

A) Often people rise to their highest level of incompetence, not their qualifications.
B) To attract the best people, the most important positions are greatly rewarded.
C) The most important positions are often filled by the most connected people.
D) No one position is more important for the survival of societies than another.