Why Have Historians Described the Democracy Created in Mid-Fifth-Century Athens

Why have historians described the democracy created in mid-fifth-century Athens under Pericles as "radical"?

A) Athens's Golden Age produced an unusual number of radical philosophers, who encouraged new ways of thinking about political power.
B) Pericles had seized control of the Athenian government by appealing to the most radical elements of the Athenian populace.
C) All male residents over the age of eighteen were allowed to vote and participate in assembly meetings.
D) All citizens, regardless of wealth, enjoyed equal protection under the law because the court system was removed from elite control.