It's A) Sentence 3, Because I don't think the heat from glass radiate
There were of course several major achievements in human history during the Old Stone Age, but by far was the use of tools, which was a major human development.
The Byzantine Empire had kept Greek and Roman culture alive for nearly a thousand years after the fall of the Roman Empire in the west. It had preserved this cultural heritage until it was taken up in the west during the Renaissance
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