Final answer:
The fate of the Nobel Prize during World War II is not mentioned in the provided information, but it is likely that the prize was returned to the original winners without any issues.
Step-by-step explanation:
The gold solution from the Nobel Prize medals was reduced back down to solid gold after World War II. However, there is no information to suggest that the Nobel Prize was permanently lost due to the war's impact on the Nobel Prize organization. The fate of the Nobel Prize awarded to the individual who safeguarded the gold medals during the war is not mentioned in the provided information. Therefore, it is most likely that the Nobel Prize was returned to the original winners without any issues, as there is no evidence to suggest otherwise.