Salesforce JavaScript Developer Practice Exam 2025 – Your All-in-One Guide to Exam Success!

The disconnectedCallback lifecycle hook in Lightning Web Components (LWC) is specifically designed to run just before a component is removed from the DOM. This means that when a component is about to be destroyed, this method allows developers to perform any necessary cleanup, such as clearing timers, cancelling API calls, or unsubscribing from events. It is an important part of component lifecycle management, ensuring that resources are properly released and avoiding memory leaks.

The other options pertain to different lifecycle events in LWC. Changes in component properties trigger the `renderedCallback` lifecycle hook, which allows developers to respond to updates after rendering. The component creation is handled by the `constructor` and `connectedCallback`, which set things up for the component when it is first instantiated. Lastly, events emitted by the component activate event handler functions rather than lifecycle hooks, so they are not related to the disconnectedCallback at all. This clarification underlines the unique role of the disconnectedCallback in managing the component's lifecycle effectively.