Question

Which storage system consists of magnetic material and may require an external power source to run?

A)CF card
B)UDO
C)SD card
D)HDD

Answer 1

Looking through my notes here I found that might be useful:

Hard drives are data storage devices used to store and retrieve digital information. An HDD stores data in rapidly rotating disks, which have magnetic material coating. An HDD retains its data even when you power it off. There are two types of HDD. Some high-capacity, high-speed hard drives require an external power source. You can connect them to your computer with a USB cable or Firewire cable connector. Others directly draw power from your computer when you connect them through a USB cable.

HDDs are available in various storage capacities, and they’re ideal for long-term storage. When you use HDDs, you need to be careful and follow the correct protocols to connect or disconnect them from your computer.

The answer is most likely D

Answer 2

The CF card is known as compact flash memory card and can be directly connected in portable devices. UDO is known as Ultra Density Optical and it is not a backward compatible. SD card is known as Secure Digital card and also used for portable devices. While HDD is known as the Hard Disk Drive and it is used to store large sizes of files. HDD needs an external power source to run.

The answer is letter D. HDD.