Hitachi
IBM
Fujitsu
Xerox
 
Correct Answer: IBM

A brief explanation why…

After looking into different technologies including wire matrices and rod arrays, IBM invented the hard disk drive at its San Jose California lab in 1953 and initially referred to the technology as a "Random Access File," which proved to be less expensive and slower than drum memory but faster and more expensive than tape drives.

The first commercial hard disk drive was shipped in 1956 as the IBM Model 350 disk storage (US Patent 3,503,060) inside the IBM 305 RAMAC system, which offered 5MB of storage at $10,000 per MB. The first disk platters had a diameter of 24 inches and were stacked 50 deep in boxes that resembled washing machines -- a far cry from today's compact 3.5" or 2.5" disks, let alone solid state drives which are coming in the even smaller M.2 form factor.