Final answer:
The PATH variable specifies the list of directories to be searched for executable files in command executions.
It defines where the system should look for the commands the user enters without need for a fully qualified path.
Therefore, the correct answer is: option "is made up of a list of directories to be searched in order when commands are executed without an absolute or relative pathname."
Step-by-step explanation:
The variable PATH is an environment variable in Unix, Linux, and other Unix-like operating systems that specifies the directories to be searched for executable files when a command is issued without a fully qualified path.
PATH contains a string of directories separated by colons . The way that PATH is used is that any executable files in the directories listed in PATH can be executed without specifying the full path to the file.
When a user types a command into the shell, the system searches through each directory in the PATH variable in the order listed to find the executable that matches the command name.
The PATH does not change the location of the PATH variable itself, it does not allow a filename as an argument to the cd (change directory) command, nor does it directly allow the use of the list of directories by the cd command.