Read the passage from The History of the Peloponnesian War by Thucydides.

If we turn to our military policy, there also we differ from our antagonists. We throw open our city to the world, and never by alien acts exclude foreigners from any opportunity of learning or observing, although the eyes of an enemy may occasionally profit by our liberality; trusting less in system and policy than to the native spirit of our citizens.

–The History of the Peloponnesian War, Thucydides

What is one distinction that Thucydides makes about Greece in this passage?

Greece excludes foreigners to keep the city-states safe.
The Greeks trust their citizens to report illegal behavior.
Greece is concerned about spies coming to the city-state during the war.
The Greeks allow foreigners to come in to observe and learn from the Greeks.