The Library of Alexandria was not destroyed in a single fire.
Why it is true
The Library of Alexandria was not destroyed in a single event. It was gradually lost over several centuries, due to fires, wars, funding cuts and the decline of the Roman Empire. Its complete destruction is still a historical mystery.
Source: National Geographic
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.