Which of the following is NOT a method of specifying?

The method of specifying in construction documents generally refers to how materials, products, and methods are described in specifications. Among the options presented, the inclusion of "procurement" in the last choice makes it an incorrect method of specifying.

Descriptive, performance, reference standard, and proprietary are all recognized methods of specifying materials and workmanship in construction. A descriptive specification outlines the exact characteristics of materials and workmanship; performance specifications define the requirements based on the outcomes or results desired; reference standard specifications use established standards as a basis for quality or performance; and proprietary specifications refer to specific brand-name products.

Procurement, on the other hand, does not fit within the realm of specifying methods as it relates more to the process of acquiring goods and services rather than detailing their characteristics or standards within construction documents. Thus, identifying procurement as a method of specifying is incorrect, making it the right choice to indicate what is NOT a method of specifying.