How do growth regulator herbicides typically move within a plant?

Growth regulator herbicides are designed to mimic natural plant hormones, which play crucial roles in plant growth and development. When applied, these herbicides are absorbed by the plant and then translocate to the growing points, such as the tips of shoots and roots, where they exert their physiological effects. This movement allows the herbicides to influence processes like cell division and elongation, ultimately disrupting normal growth patterns.

By translocating to the growing points, growth regulator herbicides can effectively alter the growth of the entire plant, leading to inhibition of shoot and root development. This targeted movement is crucial for ensuring that the herbicides achieve their intended effect on the plant's growth processes rather than being confined to localized areas, which would limit their efficacy.

In contrast, other options do not accurately reflect the behavior of growth regulator herbicides. Remaining localized would prevent the herbicides from reaching parts of the plant where they can effectively disrupt growth. Absorption only through the roots would limit the potential for the herbicides to interact with all parts of the plant. Evaporation into the air before reaching roots is inconsistent with their mode of action, as these compounds need to be inside the plant to elicit changes in growth and development.