Question

identifying advantages and disadvantages of dna technologies
crops can be genetically engineered to be herbicide resistant, allowing farmers to control weeds without harming the crops.
what is a potential disadvantage of herbicide - resistant crops?
enhanced nutritional value of crops
a reduced need for herbicides
increased crop yields per acre of land
the development of herbicide - resistant weeds

Explanation:

When herbicide - resistant crops are used, weeds are constantly exposed to herbicides. Through natural selection, weeds that have a natural resistance (due to genetic variation) to the herbicides can survive and reproduce. Over time, this can lead to the development of herbicide - resistant weed populations.
Enhanced nutritional value of crops is an advantage. A reduced need for herbicides is also an advantage as it can lower costs and potential environmental impacts from herbicide over - use. Increased crop yields per acre of land is another positive aspect.

Answer:

the development of herbicide - resistant weeds