Which of the following does NOT describe one of the four main types of specifications?

Reference standard specifications are defined precisely by basing requirements on an established published standard, making this an accurate description of a valid type.

Prescriptive specifications are defined by specifying exact material properties and installation methods, making this an accurate description of a valid type.

Proprietary specifications are defined by calling out specific brand names and model numbers, making this an accurate description of a valid type.

Performance specifications are defined by focusing on the desired end result or outcome rather than dictating methods, making this an accurate description of a valid type.

The four accepted specification types are: proprietary (identifies brand names and models), prescriptive or descriptive (specifies exact material properties and installation methods), performance (defines desired end results), and reference standard (based on an established published standard). 'Listing maximum acceptable performance' is not a recognized specification category - it describes a characteristic that could appear within a performance spec but does not constitute a standalone specification type in industry taxonomy.