Answer: An event
Explanation:
The clicking is the form of an event that basically occur when any type of elements are click.
The clicking is the function which is performed by the user in the computer system which basically activates the element so that it give some meaningful output for example keyboard and mouse.
Clocking is the event that basically attaches the function for running in the system when the click event are occurred.
Therefore, an event is the correct option.
