While instructing a patient about antibiotic therapy, the nurse explains to the patient that bacterial resistance to antibiotics can occur when: 

A. Neutrophils: Neutrophils are a type of white blood cell that plays a key role in the immune system's response to infections, particularly bacterial infections. They are not primarily involved in eliminating cancer cells.

B. Eosinophils: Eosinophils are another type of white blood cell. They are important in the immune response to parasites and are also involved in allergic reactions. While they have a role in the immune system, they are not the primary cells involved in eliminating cancer cells.

C. Platelets: Platelets, also known as thrombocytes, are not cells but rather small cell fragments. They are essential for blood clotting and do not directly participate in the immune response against cancer cells.

D. Macrophages: Macrophages are a type of white blood cell that are involved in the immune system's defense against cancer. They are phagocytes, which means they engulf and digest cellular debris, foreign substances, and cancer cells. Macrophages play a crucial role in the body's immune surveillance and response against cancer.

A. Discoloration of teeth: Tetracycline antibiotics can bind with calcium ions in teeth, leading to the development of yellow-gray-brown stains. This effect is particularly significant in developing teeth in children below the age of 8 and can result in permanent discoloration.

B. Anabolic change: This term doesn't specifically relate to the side effects of tetracycline. "Anabolic" generally refers to processes in the body that build up complex molecules from simpler ones. There's no direct connection between tetracycline and anabolic changes.

C. Cartilage damage: Tetracyclines, especially in high doses or with prolonged use, have been associated with potential adverse effects on cartilage. This is more relevant in individuals whose bones and cartilage are still growing, such as children. It can interfere with skeletal development.

D. Suppression of growth: Long-term use of tetracycline in children can interfere with bone growth and development. It can suppress the growth of bones and affect overall height. This is a significant concern when considering the use of tetracycline in pediatric patients.