Final answer:
The passage supports the claim that World War II was the deadliest war in human history, with over 25 million military and approximately 55 million civilian deaths.
Step-by-step explanation:
The claim that is supported by evidence in the passage is that World War II was the deadliest war in human history. The provided passages mention the enormous human cost, citing military deaths over 25 million and approximately 55 million civilian deaths worldwide, indicating that the war's global impact was unprecedented in terms of casualties. The text also specifically mentions high death tolls in countries like Russia and China, and outlines the significant losses sustained by the Axis powers, Germany and Japan, and the Allies, including the United States and the Soviet Union.