The correct option is B associate
The critical Micelle Concentration (CMC) is the concentration of surfactants in a solution above which micelles form. Below the CMC, surfactants in solution adsorb to a surface, lowering the surface tension, or disperse eithin the bulk. There may be an occasional micelle formed below the CMC. Likewise, above the CMC, a very limited amount of added surfactants may enter the dispersed phase or adsorb onto an interface. However, above the CMC, the vast majority of added surfactant will form micelles.