Answer: d.gene therapy
Step-by-step explanation:
Gene therapy can be define as an experimental technique in which the genome of the organism is manipulated by either introduction of new genes or by deletion of affected gene.
The following are the procedures which are done in a particular gene therapy:
1. Replacement of a particular mutated gene or allele that is responsible for causing disease or disorder in the body with a healthy or normal gene or allele.
2. Introduction of new gene or allele into the genome of the organism which can fight against the disease.
3. The transformation of normal genes into the cells of the organisms so as to keep them in the place of missing or defective genes so as to correct the genetic disorder.