Herbicides are used to kill weeds or plants growing where they are not wanted. A crop of corn has been genetically modified so that it is resistant to a type of herbicide that kills several species of weeds that commonly grow in the fields and interfere with growth of the corn crop.
Which question would help determine whether the corn is expressing the gene that provides herbicide resistance?
A. Has the herbicide caused damage to the corn?
B. Do seeds produced by the corn produce new corn plants?
C. Are the weeds in the field killed by the herbicide?
D. Are insects eating the leaves and damaging the corn plants?