Which type of events can trigger an event handler?

An event handler is designed to respond to various types of events that occur within a program or application. The correct answer encompasses the broad range of triggers that can activate an event handler, which includes both user actions and system events.

User actions, such as mouse clicks, keyboard presses, and other interactions initiated by the user, are common triggers for event handlers. These actions allow the application to respond dynamically to user input.

On the other hand, system events, such as timeouts, data availability, and other processes managed by the operating system or programming environment, can also trigger event handlers. This means that an event handler can react to conditions that are not directly initiated by the user, allowing for a more fluid and responsive application behavior.

By recognizing that both categories of events can trigger event handlers, it becomes clear that developers have the flexibility to create applications that respond to a wide variety of situations, improving interactivity and functionality.