which of the following is an example of gene therapy? a) an ear of corn contains genes that produce natural pesticides. b) a human has one allele for a normal gene and one allele for a mutated gene. c) a patient with hereditary anemia is given a normal version ofthe gene. d) protein from a healthy person is iniected into someone who cannot make that protein. e) a human protein is made in bacteria for future injection into someone who lacks it.