Okay, so maybe you are sure the OS isn't compromised, but how does the OS know if it's even running on the "bare metal" of your computer. Maybe it is running inside a virtual machine, and the *actual* OS on the computer is a malicious program that sits between your OS and the chips and circuits, distorting the data it sends and receives. This is called a "rootkit," and it's a deadass nightmare that actually exists in the actual world.
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A computer with a rootkit is a brain in a jar, a human battery in the Matrix. You, the computer user, can ask the operating system questions about its operating environment that it will answer faithfully and truthfully, and *those answers will all be wrong*, because the *actual computer* is being controlled by the rootkit and it only tells your operating system what it wants it to know.
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