Correct Answer: A

Rationale: The correct answer is A: Increased risk of liver dysfunction. Testosterone therapy can lead to liver dysfunction, including cholestatic jaundice and hepatitis. This adverse effect necessitates monitoring of liver function tests during testosterone therapy. Choice B, increased risk of prostate cancer, is incorrect because testosterone therapy does not cause prostate cancer but is contraindicated in patients with known or suspected prostate cancer. Choice C, increased risk of bone fractures, is incorrect as testosterone therapy is actually associated with an increase in bone mineral density, reducing the risk of fractures. Choice D, increased risk of breast cancer, is incorrect because testosterone therapy in males does not increase the risk of breast cancer.

Correct Answer: B

Rationale: Cytotoxic T cells are the key players in cell-mediated immunity as they directly attack cells displaying specific antigens. Lymphokine-producing cells (Choice A) are involved in cytokine production, while Helper T cells (Choice C) assist in activating other immune cells. Macrophages (Choice D) are phagocytic cells that engulf and digest pathogens, but they are not the primary cells responsible for directly attacking cells with specific antigens in cell-mediated immunity.

Correct Answer: B

Rationale: Swelling during acute inflammation is primarily caused by the accumulation of fluid exudate in the affected tissues. This fluid exudate contains proteins and cells that leak from blood vessels due to increased vascular permeability. Collagenase (Choice A) is an enzyme that breaks down collagen and is not directly responsible for swelling. Lymphocytic margination (Choice C) is the process where white blood cells line up along the blood vessel walls, which does not directly cause swelling. Anaerobic glycolysis (Choice D) is a metabolic process that occurs in the absence of oxygen and is not related to the mechanism of swelling in acute inflammation.

Correct Answer: C

Rationale: The correct answer is C. In assessing a child for migraines, asking about food allergies is least likely to yield data that will confirm or rule out migraines as the cause of his headaches. Food allergies are unrelated to the typical symptoms and triggers of migraines, such as family history, associated symptoms like nausea and vomiting, and pain-free intervals between headaches. Therefore, in this scenario, focusing on food allergies is less relevant for identifying migraines as the cause of the boy's headaches.

Correct Answer: B

Rationale: The correct answer is B: Decreased number of infections. Granulocyte colony-stimulating factor (G-CSF) is a medication used to stimulate the production of white blood cells, specifically granulocytes, in the body. By increasing the number of white blood cells, G-CSF helps in boosting the immune system, leading to a decreased number of infections. Choice A is incorrect as G-CSF does not cause a reduction in red blood cell count. Choice C is incorrect as G-CSF primarily affects white blood cells and is not directly related to fatigue or energy levels. Choice D is incorrect as G-CSF does increase the white blood cell count but does not usually elevate it to 20,000 mm3.