What does the term 'Entablature' refer to in classical architecture?

The term 'Entablature' in classical architecture specifically refers to a continuous horizontal lintel that sits above the columns and supports the roof or upper structure of a building. An entablature typically consists of three main sections: the architrave, frieze, and cornice. This architectural element plays a critical role in both the structural integrity and aesthetic appeal of a classical building, as it helps distribute weight from the roof down to the columns, all while adding a pronounced horizontal element to the design.

The other options pertain to different architectural features. A freestanding column would be a vertical support that stands independently, while a type of roof ornament might reflect decorative elements on the rooftop, and a type of decorative wall would involve vertical surfaces adorned with design elements. None of these encapsulate the specific function or characteristic of the entablature as the continuous horizontal lintel crucial to classical architecture.