New evidence suggests that the collapse of Egypt's old kingdom some 4,000 years ago was caused by environmental catastrophe rather than internal social upheaval. █████ █████████ ██████ █ ██████ ██ ██████ ███████ ██ ███ █████ █ █████████ █████████ ██████████ ████ ████████ █████████ █████ █████ ██ ██████ ███████ ██████ ████████ ██ █████ ██ ███ █████ ███ ████ ████████ ████ █ ██████ ███ ██████
The author argues that Egypt’s old kingdom collapsed because of climate catastrophe, not internal social upheaval. This is because ocean sediments show that global cooling caused a dry spell at the time of the collapse, which was the ultimate cause of the social problems that also existed.
The author assumes that even though climate catastrophe caused social problems in Egypt, it was climate catastrophe, and not these social problems, that was the "real" cause of the old kingdom's collapse. This seems to rule out the possibility that social problems were a secondary or more direct cause of the collapse, or assume that only the first cause of an event is the "real" cause.
Which one of the following, ██ █████ █████ ████ ██████████ ███ █████████
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Egyptian records recovered ████ ███ ████ ██ ███ ████████ ██████████ █████ ██ ███ █████████████ ██████████ ██ ███ ████████
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