Correct Answer: A

Rationale: The correct answer is A. Parkinson's disease is caused by a deficiency of dopamine in the brain, which results in the characteristic motor symptoms such as tremors, rigidity, and bradykinesia. Choice B is incorrect because Parkinson's disease is not caused by an excess of acetylcholine. Choice C is incorrect because Parkinson's disease is not an autoimmune disorder. Choice D is incorrect because Parkinson's disease is not caused by a bacterial infection and cannot be treated with antibiotics.

Correct Answer: A

Rationale: During the vascular stage of inflammation, there is an outpouring of exudate into the interstitial spaces, leading to swelling and edema. Choice B, chemotaxis, occurs during the cellular stage of inflammation, where leukocytes move to the site of injury in response to chemical signals. Choice C, accumulation of leukocytes along the epithelium, is not a typical event during the vascular stage. Phagocytosis of cellular debris, as in choice D, mainly occurs during the resolution stage of inflammation.

Correct Answer: B

Rationale: The correct answer is B: Use of nitrates. Sildenafil (Viagra) is contraindicated in patients taking nitrates due to the risk of severe hypotension. Nitrates combined with sildenafil can lead to a dangerous drop in blood pressure. Choices A, C, and D are incorrect because a history of peptic ulcer disease, use of antihypertensive medications, or a history of hypertension are not direct contraindications for sildenafil use.

Correct Answer: A

Rationale: The correct answer is A: Hepatotoxicity. Androgen therapy, such as testosterone, can lead to hepatotoxicity, which is toxic to the liver. Therefore, the nurse should monitor the patient's liver function. Choices B, C, and D are incorrect because androgen therapy is not typically associated with nephrotoxicity, cardiotoxicity, or pulmonary toxicity.

Correct Answer: D

Rationale: The correct answer is D, Rigor mortis. Rigor mortis is the stiffening of muscles after death, typically beginning within 6 to 14 hours. Livor mortis (choice A) refers to the pooling of blood in the lowest tissues causing discoloration, gangrene (choice B) is the death of body tissue due to lack of blood flow, and algor mortis (choice C) is the cooling of the body after death.