Correct Answer: B

Rationale: In this scenario, where impaired erythropoiesis is suspected, the most clinically relevant laboratory studies would focus on red blood cell parameters. Therefore, assessing RBC count, hemoglobin levels, and hematocrit values would provide direct insights into erythropoiesis. Choices A, C, and D are not directly related to erythropoiesis assessment. White blood cell count with a differential is more indicative of immune response and infection. INR and aPTT are coagulation studies, while d-dimer and C-reactive protein levels are more associated with inflammation and thrombotic events.

Correct Answer: A

Rationale: The correct answer is A. Tamoxifen is known to increase the risk of venous thromboembolism, a serious side effect. Patients should be educated about the signs and symptoms of blood clots, such as swelling, pain, or redness in the affected limb, and the importance of seeking immediate medical attention if they occur. Choice B is incorrect because hot flashes are a common side effect of tamoxifen but not a critical concern like venous thromboembolism. Choice C is incorrect as tamoxifen is not associated with a decreased risk of osteoporosis. Choice D is incorrect because while weight gain can occur with tamoxifen, it is not as crucial to educate the patient about as the risk of venous thromboembolism.

Correct Answer: B

Rationale: Asking about a history of recent head injury is less likely to yield data relevant to confirming or ruling out migraines. Migraines are often associated with symptoms like nausea, vomiting, sensitivity to light, and a family history of migraines. While head injuries can cause headaches, the focus of the assessment in this case should be on symptoms more specific to migraines to guide the diagnosis and management.

Correct Answer: C

Rationale: In a client with a pneumothorax receiving oxygen therapy, improved breath sounds on the affected side would indicate effective treatment. This finding suggests that the collapsed lung is re-expanding, allowing air to flow more freely in and out of the affected area. Choices A, B, and D are incorrect: Increased respiratory rate, decreased oxygen saturation levels, and increased dyspnea and chest pain are signs of ineffective treatment or worsening of the condition in a client with a pneumothorax.

Correct Answer: B

Rationale: The correct answer is B: 'Do not take more than one dose in a 24-hour period.' It is essential for the nurse to emphasize this instruction to prevent potential adverse effects from taking multiple doses of sildenafil. Choice A is incorrect because sildenafil should be taken approximately 30 minutes to 4 hours before sexual activity, not specifically 1 hour before. Choice C is important but not the priority; while vision or hearing loss are potential serious side effects of sildenafil, the immediate concern should be focused on dose frequency. Choice D is incorrect as sildenafil can be taken with or without food.