Most of unplanned downtime of information systems is attributed to which of the following?

A.
Hardware failure

B.
Natural disaster

C.
Human error

D.
Software failure

Explanation:
This is what the static’s says. Most of the downtime is cause of unexpected
hardware failure. Commonly you just replace the FRU (Field replazable unit) when they fail.
Usually a well written software does not fail if the hardware is running correctly. The human errors
are controllable and natural disasters are not very often. Hardware failure is very common, it’s a
good practice to have spare disks, NIC and any other hardware FRU´s in your company to
minimize the downtime with quick replacements.