The correct answer is A. 20 MB.
The IBM PC-XT was the first personal computer to include a hard drive. It was released in 1982 and had a hard drive capacity of 20 MB. This was a significant increase in storage capacity compared to the floppy disks that were previously used to store data on personal computers. The hard drive allowed users to store more programs and data on their computers, which made them more powerful and versatile.
The other options are incorrect. Option B, 1.44 MB, is the capacity of a standard floppy disk. Option C, 10 MB, is the capacity of a hard drive that was released a few years after the IBM PC-XT. Option D, 750 KB, is the capacity of a floppy disk that was released before the IBM PC-XT.
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