Which is an example of a common good?

For which of the following was Plato not criticized?

a. Hostility toward democracy b. Support of censorship c. Advocating a rigid class society d. Reluctance to move from opinion to knowledge

If top political jobs for both political parties are filled only from an inner circle of top corporate leaders, this would be evidence for which of the following?

A. Elite theory B. Substantive democracy C. Pluralist theory D. The interest group model E. Authoritarianism