A farmer uses triazine herbicide to control pigweed in his field.For the first few years,the triazine works well and almost all the pigweed dies;but after several years,the farmer sees more and more pigweed.Which of these explanations best describes this observation?
A)The herbicide company lost its triazine formula and started selling poor-quality triazine.
B)Natural selection caused the pigweed to mutate,creating a new triazine-resistant species.
C)Triazine-resistant pigweed has less-efficient photosynthesis metabolism.
D)Only triazine-resistant weeds survived and reproduced,so each year more pigweed was triazine-resistant.

Question

Quizplus · Accepted Answer

Over time, the only pigweed that survived and reproduced were those that were resistant to triazine herbicide. This led to an increase in the population of triazine-resistant pigweed.

A Farmer Uses Triazine Herbicide to Control Pigweed in His