The correct answer is D. The Spartans worked to stop a second Persian invasión of Greece.
Explanation
The battle of the Thermopylae was a battle of the Second Greco-Persian Wars, this battle took place in the narrow passage of Thermopylae in the middle of 480 A.C. and lasted seven days. It started when the Persian led by Xerxes I, wanted to dominate the Greece territory through invasion. As a reaction, several Greek Polis were allied, including Sparta and Athens. Those greek people fought against the Persians to stop the second invasion of the Persian Empire. So, the correct answer is D. The Spartans worked to stop a second Persian invasion of Greece.
The main cause for this was so that Germany was left divided in power. Since each sub-part of Germany lacked the powe to mount another army, it was a strategic move done in the best interest to secure world peace.
This is because both countries sought to have influence around the world. After the World War II, Russia sought to spread its Communism ideology in various spheres of the world whereas the Western powers, Britain included sought to spread the ideals of capitalism
