Question

for over a decade, farmers in the u.s. have been planting genetically modified crops. an example of one of these crops is corn that is resistant to weed - killer. this makes it so that no corn is lost due to contact with herbicide meant to kill weeds. while this is seen by many as a positive development, others see it as a cause for concern. what is one possible negative side effect of planting corn that is resistant to weed - killer? a genetically modified corn, as well as other plants, is unnatural. b corn will replace wheat and other crops as our main source of carbohydrates. c plants with modified genomes may have an unforeseen impact on the environment. d the resistance gene could be transferred to actual weeds, making farming more difficult. e the corn that is resistant to weed - killer will eventually revert back to its original state and the corn crop will lost.

Explanation:

Genetically modified crops with weed-killer resistance can have genes transferred to weeds via cross-pollination or horizontal transfer, making weeds resistant and farming harder. This is a specific, documented negative effect.

Answer:

D. The resistance gene could be transferred to actual weeds, making farming more difficult.