Correct Answer: C

Rationale: The main rationale for administering a nucleotide reverse transcriptase inhibitor in combination with a nonnucleotide reverse transcriptase inhibitor is that they exhibit synergistic antiviral effects when used together. This combination enhances their antiviral activity against HIV by targeting different steps in the viral replication cycle. Choice A is incorrect because the rationale for combining these medications is based on their antiviral effects, not treatment adherence. Choice B is incorrect because the primary purpose of combination therapy is not to reduce the duration of illness but to improve treatment efficacy. Choice D is incorrect as the main focus of this combination is not on preventing opportunistic infections but on directly targeting the HIV virus.

Correct Answer: C

Rationale: The main rationale for administering a nucleotide reverse transcriptase inhibitor in combination with a nonnucleotide reverse transcriptase inhibitor is that they exhibit synergistic antiviral effects when used together. This combination enhances their antiviral activity against HIV by targeting different steps in the viral replication cycle. Choice A is incorrect because the rationale for combining these medications is based on their antiviral effects, not treatment adherence. Choice B is incorrect because the primary purpose of combination therapy is not to reduce the duration of illness but to improve treatment efficacy. Choice D is incorrect as the main focus of this combination is not on preventing opportunistic infections but on directly targeting the HIV virus.

Correct Answer: C

Rationale: The correct answer is C: PH 7.40, PaCO2 40 mm Hg, PaO2 90 mm Hg, HCO3 24 mEq/L. These values represent a balanced state for arterial blood gas. Choice A has lower than normal PH and HCO3 levels and higher PaCO2 and lower PaO2 levels. Choice B has higher than normal PH and HCO3 levels, lower PaCO2, and a normal PaO2 level. Choice D has a significantly lower PH and PaO2 level, normal HCO3 level, and low PaCO2 level, indicating an acidic state with impaired oxygenation.

Correct Answer: B

Rationale: In acute respiratory failure, hypoxemia (low blood oxygen) and hypercapnia (high blood carbon dioxide) are commonly observed. Choice A is incorrect because alkalosis (high pH) and hyperventilation are not typically seen in acute respiratory failure. Choice C is incorrect as it mentions alkalosis and high potassium, which are not characteristic of acute respiratory failure. Choice D is also incorrect because elevated sodium and acidosis are not typically associated with acute respiratory failure.

Correct Answer: C

Rationale: Estrogen is the correct answer. Amenorrhea, the absence of menstruation, is often due to hormonal imbalances. Estrogen plays a crucial role in regulating the menstrual cycle. Prescribing estrogen can help address these hormonal imbalances and restore menstrual cycles. Testosterone (Choice A) is not typically prescribed for amenorrhea in women as it can further disrupt hormonal balance. Follicle-stimulating hormone (Choice B) is involved in stimulating ovulation and follicle development, not the primary treatment for amenorrhea. Lactate (Choice D) is not a medication used to treat amenorrhea.