How are HTML attributes specified within an element?

HTML attributes are specified within an element by setting name-value pairs in the opening tag. This means that when you create an HTML element, you can include additional information using attributes, which are defined using a specific syntax.

For example, in the tag <img src="image.png" alt="An image description">, the src and alt are attributes of the <img> element. The src attribute specifies the source of the image file, while the alt attribute provides alternative text describing the image. Each attribute consists of a name (like src or alt) followed by an equal sign and a value, all enclosed in quotation marks.

Using separate attributes tags inside the element is not how HTML attributes are structured; instead, they are directly included in the opening tag itself. Enclosing attributes in curly braces is not part of standard HTML syntax; this syntax might be found in JavaScript or templating languages. Referencing attributes in a stylesheet pertains to CSS styling and does not define attributes within the HTML element itself.

Thus, specifying attributes as name-value pairs within the opening tag is essential for defining properties and behaviors of HTML elements.