Young Helmholtz theory is associated with which of the following?

The Young-Helmholtz theory of color vision in humans postulates the existence of three kinds of cones, each containing a different photopigment and that are maximally sensitive to one of the three primary colors, with the sensation of any given color being determined by the relative frequency of the impulses from each of these cone systems. Ref: Ganong's Review of Medical Physiology 23rd edition, Chapter 12.