What Finally Led to Athenian Defeat and the Conclusion of the Peloponnesian

What finally led to Athenian defeat and the conclusion of the Peloponnesian War?

A) Frustrated by more than two decades of nearly constant warfare and a devastating outbreak of the plague, the Athenian population revolted and installed a government that sued for peace.
B) The Spartans forged an alliance with a small number of the wealthiest Athenians, who embraced Spartan rule in order to realize their goal of destroying Athenian democracy.
C) The Spartans finally succeeded in conquering the overland routes to Athens and starving the city into submission.
D) The Spartans enlisted the help of the Persians to build a navy that could force the Athenians to surrender.