What was the significance of the battle of marathon?
a. the persians defeated the athenians and took over all of ancient greece.
b. the persians conquered the athenians but were soon stopped by the spartans. c. the athenians conquered the persians and overthrew king darius i.
d. the athenians defeated the persians and halted an invasion by king darius i.

The correct answer is D, as the Athenians defeated the Persians and halted an invasion by King Darius I.

The battle of Marathon was an armed confrontation that defined the outcome of the First Medical War. It happened in the year 490 a. C. and took place in the fields and the beach of the city of Marathon, located a few kilometers from Athens, on the east coast of Attica. It faced on the one hand the Persian king Darius I, who wanted to invade and conquer Athens for his participation in the Ionian revolt, and, on the other hand, the Athenians and their allies (Platea, among others). A feat recalled in this battle by Heródoto was the one of Filípides, that crossed the way of Athens to Sparta to request aid to the Spartan army. Sparta refused to help the Athenians, claiming to be on dates of religious celebrations.

After the revolt of Ionia, Darius decided to punish the Greek city that had lent aid to his rebellious subjects. After taking Naxos and Eretria, the Persian expedition, with the advice of Hippias, who hoped to regain power in Athens, disembarked on the beach of Marathon. After five days face to face, the Athenian and Platan phalanges crushed the Persian infantrymen who fled and embarked again with heavy casualties. The Greek army quickly withdrew to Athens to prevent the landing of the other part of the Persian expeditionary corps in Falero, one of the city's ports.

This victory put an end to the First Medical War. Ten years later, a new attack took place on the orders of Xerxes I. The battle of Marathon played an important political role by affirming the Athenian democratic model and the beginning of great military careers for Athenian generals like Miltiades or Aristides the Just.

i think it was   tsar alexander ii