Which of the following is NOT related to the measurement of paper?

The measurement of paper primarily involves aspects such as physical dimensions, weight, and quantity, typically denoted by specific terminology. Binding refers to the process of assembling sheets of paper, which can involve various measurements, such as thickness and spine width, but is essential for understanding how paper can be compiled. A ream is a standard unit of measurement for quantities of paper, usually consisting of 500 sheets. Grayscale pertains to the range of shades of gray in an image and is related to the quality of printed images or graphics but not to the physical measurement of paper itself.

Pixels, while critical in digital design and image resolution, do not serve as a measurement for paper. Therefore, the association of pixels is distinctly separate from the physical characteristics associated with paper measurement, making it the correct choice that is not related to the measurement of paper.