Correct Answer: C

Rationale: A tension pneumothorax is characterized by a large accumulation of trapped air in the pleural space, creating pressure that affects both the lungs and heart. This condition can lead to life-threatening consequences by shifting mediastinal structures and impairing cardiac function. Treatment involves decompressing the trapped air to relieve the tension. Choices A, B, and D are incorrect as they do not describe the primary pathophysiological mechanism of tension pneumothorax, which is the accumulation of air in the pleural space, not blood, rib fractures, or alveolar fluid accumulation.

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: D

Rationale: The correct answer is D: 'Symptom.' Dizziness is a symptom because it is a subjective experience reported by the patient. A 'contraindication' refers to a specific situation in which a drug, procedure, or surgery should not be used because it may be harmful. A 'sign' is an objective finding that can be observed or measured. 'Objective data' refers to measurable and observable information about a patient's condition, which is usually obtained through physical examination or diagnostic tests. Therefore, in this case, 'Symptom' is the best term to describe the patient's feeling of dizziness.

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: B

Rationale: The correct statements about secondary immunodeficiencies are that they may develop after viral infections, following immunosuppressive therapies, and are caused by superimposed conditions. Choice B ('Develop before birth') is incorrect because secondary immunodeficiencies do not develop before birth. They are acquired later in life. Therefore, the correct answers are A, C, and D.