Which of the following is a type of storage device that typically utilizes magnetic disks?

The Hard Disk Drive (HDD) is a type of storage device that employs magnetic disks to record and retrieve digital information. Inside an HDD, data is stored on rotating platters coated with a magnetic material. A read/write head moves over these platters to access the information, which is why HDDs are well-known for their capacity to store large amounts of data at a relatively low cost compared to other storage types.

On the other hand, flash drives, cloud storage, and external SSDs utilize different technologies. Flash drives use flash memory, which is non-volatile and does not require moving parts. Cloud storage refers to storing data on remote servers accessed via the internet, meaning the actual storage medium is not physical on the user's premises. External SSDs (Solid State Drives) rely on solid-state technology, which is based on flash memory rather than magnetic disks. Thus, while HDDs are distinguished by their magnetic disk technology, the other options are based on different storage mechanisms.