Which category of herbicides is absorbed by the plant and then translocated through its systems?

The correct choice is translocated/growth regulators. This category of herbicides works by being absorbed through the plant's foliage or roots and then moved throughout the plant's systems. This system-wide movement allows the herbicide to target and affect various physiological processes, often leading to the death of the plant by disrupting growth regulation.

Translocated herbicides are particularly effective because they can reach internal tissues, impacting both actively growing parts and dormant areas. The herbicide's ability to move ensures that it can affect the entire plant, not just the parts that come into direct contact with the spray. This makes them effective against perennial weeds and various unwanted vegetation that may not be easily controlled through methods that only affect surface contact.

Contact herbicides, in contrast, only affect the parts of the plant they come into direct contact with and do not move through the plant. Selective herbicides target specific types of plants, but they may not necessarily translocate throughout the plant in the same way. Residual herbicides persist in the soil and can control weed growth over time but are not absorbed and translocated within the plant like translocated/growth regulators.

The effectiveness of translocated herbicides in managing unwanted plant growth lies in their ability to integrate through the plant's