Final answer:
Among the options provided, chemotherapy is not an example of a biological therapy. Option 3 is correct.
Step-by-step explanation:
All of the following are examples of biological therapies except chemotherapy. Biological therapies include techniques such as gene therapy, immunotherapy, and hormone therapy. These therapies use the body's biological mechanisms to treat diseases.
Gene therapy involves introducing foreign DNA to cure inheritable diseases. Immunotherapy helps the immune system fight cancer, using methods like the application of monoclonal antibodies or therapeutic vaccines to enhance the immune response against cancer cells. Hormone therapy often involves supplementing or inhibiting natural hormones to treat various conditions, such as cancer or hormone-related disorders.
In contrast, chemotherapy typically refers to the use of chemical substances, specifically anti-cancer drugs, to kill or inhibit the growth of cancer cells. It's a form of treatment that doesn't specifically use the body's biological processes, but rather uses cytotoxic chemicals to directly target and destroy cancer cells.
Gene therapy, immunotherapy, and hormone therapy all utilize the body's biological processes to treat diseases, while chemotherapy involves chemical drugs to attack cancer cells.