Some Critics of GM agriculture fear that GM plants resistance to herbicides could result in the overuse of toxic chemical ?why this may happen

See the answer below

Explanation:

Genetically modified plants specially designed to be be resistant to herbicides could actually result in the overuse of toxic chemicals.

Herbicides are agrochemicals that primarily function to kill weeds but have the capability to kill any other susceptible plants. While some herbicides are specific for grasses or broad-leaf plants, some are general and kill both broad-leafed and grass plants.

Several herbicides are toxic to the environment in terms of being poisonous to non-target organisms and polluting the environment generally.

Farmers are usually more careful in administering herbicides when the farmland is filled with crops that are also susceptible to the herbicide.  A farmland filled with genetically modified crops that is built to be resistant to herbicide may result in indiscriminate use of herbicides by the farmer.

Indiscriminate use of herbicides will have a serious ecological effects on the environment.

the correct answer to this question is #5