Top is a utility that has the following function:

A.
managing process

B.
managing swap file

C.
managing permissions

D.
this utility does not exist

Explanation:
Top provides an ongoing look at processor activity in realtime. It displays a listing of the
most CPU-intensive tasks on the system, and can provide an interactive inter- face for
manipulating processes. It can sort the tasks by CPU usage, memory usage and runtime.
can be better configured than the standard top from the procps suite. Most features can
either be selected by an interactive command or by specifying the feature in the personal
or system-wide configuration file. See below for more information.