What caused the Greeks to unify in defense of their culture and way of life?(1 point) Responses the attempt of Athens to force democracy on all the poleis the attempt of Athens to force democracy on all the poleis the invasion of Corinth by Thermopylae the invasion of Corinth by Thermopylae the attempt by Sparta to control all of Greece the attempt by Sparta to control all of Greece the threat of the Persian Empire conquering Greece