Which definition will AEM pick for a decorative tag defined for a component?

The definition selected by AEM for a decorative tag defined for a component is derived from the TagName defined using the @ decoration TagName attribute in HTL. This is because HTL (Hypertext Template Language), which is the templating engine used in AEM, allows for specific decoration attributes that can directly influence how components are rendered in the DOM.

When you declare a decorative tag using the appropriate TagName attribute in HTL, you are instructing AEM to apply that decorative element during the rendering process. This is essential for managing the structure and semantics of the HTML output, which can impact both the presentation layer and SEO.

The other options do provide some relevant aspects concerning the component configuration in AEM, but they do not specifically pertain to how the decorative tag is set during the rendering phase in a way that overrides or complements the processing done in HTL. For example, properties like cq:htmlTag may be associated with other component attributes but do not have the same focus on decoration as the HTL syntax does. Similarly, the TagName property on the component policy node and the default settings in AEM generally serve broader purposes and don’t directly equate to the specific use-case of decorating tags during the rendering process.