Correct Answer: A

Rationale: When educating a patient starting on oral contraceptives, it is essential to stress the importance of taking the medication at the same time each day. This ensures stable hormone levels, improving the effectiveness of the contraceptives in preventing pregnancy. Choice B is incorrect because consistency in timing is crucial for maintaining hormone levels. Choice C is incorrect as there is no specific requirement to take oral contraceptives in the morning to avoid side effects. Choice D is incorrect as oral contraceptives may take some time to become fully effective, and consistent timing is important for their efficacy.

Correct Answer: D

Rationale: When serotonin levels increase, more neurotransmitters will cross the synaptic cleft and bind with postsynaptic receptors, facilitating enhanced communication. Option A is incorrect because chemical synapses, unlike electrical synapses, are unidirectional. Option B is incorrect because neurotransmitters impact communication with multiple neurons, not just a single connected neuron. Option C is incorrect because neurotransmitters cross the synaptic cleft, not gap junctions.

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 and sildenafil both cause vasodilation, and their combined use can lead to a dangerous drop in blood pressure. Choices A, C, and D are incorrect because a history of hypertension, recent use of antihypertensive medications, or a history of peptic ulcer disease are not direct contraindications for using sildenafil.

Correct Answer: B

Rationale: The correct answer is B: Smoking. Smoking is the primary risk factor for developing lung cancer. Tobacco smoke contains numerous carcinogens that can damage the cells in the lungs, leading to the development of cancer. Alcohol consumption (Choice A), poor diet (Choice C), and environmental exposure (Choice D) can contribute to overall health risks, but they are not the primary risk factors specifically associated with the development of lung cancer.

Correct Answer: A

Rationale: Before administering iodoquinol (Yodoxin), the nurse should assess for allergy to iodine since iodoquinol is a medication containing iodine. Assessing for skin eruptions (choice C) and ophthalmic symptoms (choice D) are not specifically related to iodoquinol administration. Noting the time the patient last ate (choice B) may be relevant for certain medications but is not directly related to assessing for an allergy to iodine in this case.