Which attribute is used with the <a> tag to specify the destination URL?

The attribute used with the <a> tag to specify the destination URL is href. This attribute is essential because it indicates the address of the webpage or resource to which the hyperlink points. When a user clicks on the link, the browser navigates to the URL specified in the href attribute. This is a fundamental aspect of creating hyperlinks in HTML, allowing for connectivity between different pages or external sites.

Other attributes like src, link, and url do not serve this specific function in the context of the <a> tag. For instance, src is typically used with elements like <img> to specify the source of an image. Therefore, understanding the role of the href attribute is crucial for building effective and functional hyperlinks in web design.