Farmers raise crops that have been made virus-resistant by adding a gene from the teosinte weed. This is an example of... * natural selection.
gene therapy.
genetically modified organisms.
artificial selection.

i think the answer is b.

hope it

he forelimbs below belong to four species that descended in a direct line from the ancestral mammal shown above. of the four descendants shown, which species most likely appeared earliest in evolutionary history?