A technique used to repair the defective genes?

Explanation

The correct answer is gene therapy. This technique involves altering the genes inside a person's cells to treat or stop disease, directly addressing genetic defects at the molecular level. In contrast, integrated disease management focuses on managing diseases using various methods without altering genetic material. Bioremediation deals with cleaning up environmental contaminants using organisms, and cloning is about creating identical copies of organisms or cells, neither of which involves repairing defective genes.