What Is the General Procedure for Carrying Out Somatic Gene

What is the general procedure for carrying out somatic gene therapy?

A) The dysfunctional genes are excised from the egg and sperm cells of the parents and replaced with correctly functioning versions such that any resulting embryos are healthy.
B) A properly functioning version of the dysfunctional gene causing a disorder is injected into a virus and the virus then infects the cells of the patient, thus giving them a working copy of the gene and treating the disease.
C) A dysfunctional gene causing a disorder in a patient is fixed via mutation such that it works again, thus treating the disease.
D) The dysfunctional genes causing a disorder in a patient are excised from his or her cells and correctly functioning genes are injected in via a virus, thus treating the disease.
E) Prenatal screening is done to identify dysfunctional genes, and these are excised from the embryo's cells and replaced with properly functioning genes, thus treating a potential disease.