Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information. A. Cleisthenes, a reformer who recognized that aristocratic control had been decreasing since the end of the previous century, finally drove the tyrants out of Athens in 508 B.C. B. The tyrants were driven out, and in 508 B.C. Cleisthenes put in place the structures that completed the weakening of the aristocracy. C. By driving out the tyrants, Cleisthenes enabled the reforms that had been under way since the end of the century to reach their final form in 508 B.C. D. Toward the end of the century, the tyrants were driven out, and in 508 B.C. Cleisthenes saw that it was time to change the structures that had reduced aristocratic control.