Which of the Following Is an Example of Gene Therapy

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 of the gene.
D) Protein from a healthy person is injected into someone who cannot make that protein.
E) A human protein is made in bacteria for future injection into someone who lacks it.