Correct Answer: A

Rationale: The correct answer is Clarithromycin. Clarithromycin is one of the recommended medications for treating Mycobacterium avium complex (MAC) infections in patients with HIV. It is a macrolide antibiotic that is effective against MAC. Isoniazid (INH) is used to treat tuberculosis, not MAC. Rifabutin is another medication used in the treatment of MAC infections, but clarithromycin is preferred as a first-line agent. Azithromycin is also used in the treatment of MAC infections; however, clarithromycin is more commonly recommended due to its efficacy and safety profile.

Correct Answer: A

Rationale: In a person diagnosed with AIDS, a decrease in CD4 helper T cells is expected. These cells are critical for the immune system's proper functioning, and their reduction weakens the body's ability to fight infections. CD8 helper T cells (Choice B) are not typically decreased in AIDS. CDC cells (Choice C) and CDC10 cells (Choice D) are not relevant terms in this context, making them incorrect choices.

Correct Answer: C

Rationale: The correct answer is C: Organ transplantation. Immunosuppressant agents are commonly used in organ transplant recipients to prevent organ rejection by suppressing the immune system. Choices A, B, and D are incorrect. Intractable seizure disorders are often managed with antiepileptic drugs, increased intracranial pressure is managed through various means like surgery and medications, and HIV/AIDS with multiple drug resistance is typically treated with antiretroviral therapy, not immunosuppressant agents.

Correct Answer: C

Rationale: Corrected Rationale: Peritonitis can lead to severe complications such as sepsis and shock due to the infection spreading in the abdominal cavity. Sepsis is a systemic inflammatory response to infection, and shock is a life-threatening condition where the body's organs are not receiving enough blood flow. Choices A, B, and D are incorrect. Increased peristalsis is not a typical complication of peritonitis; dizziness and malaise, as well as nausea and vomiting, are symptoms rather than complications of the condition.

Correct Answer: C

Rationale: During the cellular stage of acute inflammation, neutrophils are the first responders. Neutrophils arrive at the site of injury in large numbers to combat pathogens and remove debris. Basophils and lymphocytes are also involved in the inflammatory response, but they are not the first to arrive. Platelets play a role in hemostasis and blood clotting, rather than being the primary cells involved in the initial inflammatory response.