The correct answers are A and C , as the defeat by Sparta and a plague during the war led to the end of Athens' power and greatest glory.
The resentment of other cities for the hegemony of Athens, led to the Peloponnesian War in 431 BC. Athenians and their maritime empire faced off against a coalition of states led by Sparta. This conflict marked the end of Athenian glory and the beginning of Sparta as the greatest power in Greece, at which time the government of the "Thirty Tyrants" was established.
The Athens' greatest glory was also ended by the Plague of Athens, that was a devastating epidemic that affected mainly the city-state of Athens in the year 430 BC, in the second year of the Peloponnesian War. It is believed that it must have arrived in Athens through Piraeus, the port of the city and the only source of food and supplies.
