HELLPP Identify one reason Rome fell to invaders

Invasions by Barbarian tribes The most straightforward theory for Western Rome's collapse pins the fall on a string of military losses sustained against outside forces. Rome had tangled with Germanic tribes for centuries, but by the 300s “barbarian” groups like the Goths had encroached beyond the Empire's borders.

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The fall of the Western Roman Empire was the process of decline in the Western Roman ... Despite its aqueducts, the water supply did not allow good hygiene, and sewage was disposed of on the streets, in open drain so technically by sickness

where is the passage