What is the purpose of connectedCallback in a Lightning web component?

 The connectedCallback is a lifecycle hook that is invoked when a Lightning web component is inserted into the DOM. It is used to perform any initialization tasks that depend on the component being rendered, such as fetching data, setting up event listeners, or creating timers. The connectedCallback can fire more than once, for example, when a component is moved or rerendered. The connectedCallback should not be used to change the state of a component, such as loading values or setting properties. Use getters and setters instead. The other options are incorrect because they do not describe the purpose of the connectedCallback. References: Lifecycle Hooks | Lightning Web Components Developer Guide, connectedCallback() in Lightning Web Component - Salesforce Diaries, Chapter 23: connnectedCallback() in Lightning Web Component