Correct Answer: C

Rationale: Tuberculosis, caused by Mycobacterium tuberculosis, primarily affects the respiratory system. This aerobic bacillus thrives in highly oxygenated body sites, such as the lungs, growing ends of bones, and the brain. The bacillus is airborne, making the lungs a common site for infection. Choices A, B, and D are incorrect as tuberculosis predominantly impacts the respiratory system and rarely involves the stomach, heart, or skin.

Correct Answer: C

Rationale: The correct answer is C. HIV integrates its genetic material into the host cell's DNA. The virus uses the enzyme reverse transcriptase to make a DNA copy of its RNA, which is then inserted into the genetic material of the infected cell. Choice A is incorrect because the presence of antibodies does not indicate immunity to HIV but rather exposure to the virus. Choice B is incorrect as HIV replication occurs intracellularly, inside the host cell. Choice D is irrelevant to the characteristics of HIV.

Correct Answer: D

Rationale: The correct answer is that multiple births (usually twins) occur in a small percentage (8% - 10%) of clomiphene-facilitated pregnancies. The couple should be informed about this potential outcome. Clomiphene is available in 50-mg tablets for oral use; there is no intravenous form of the medication. Breast engorgement is a common side effect of clomiphene that typically resolves after discontinuation of the medication. Ovulation usually happens 5 to 10 days after the last dose of clomiphene, and the couple is advised to engage in coitus at least every other day during this time. Therefore, choices A, B, and C are incorrect as they do not provide accurate information regarding clomiphene treatment for infertility.

Correct Answer: B

Rationale: The correct answer is the patient who received an upper extremity cast yesterday and reports not being able to feel their fingers in the right hand. This situation indicates a potential neurovascular issue that requires immediate attention to prevent complications. The other options are of lesser priority: A - Breakdown of the heels, while concerning, is not an acute issue that necessitates immediate intervention. C - An ankle sprain that occurred two weeks ago is now subacute and unlikely to be an urgent medical concern. D - Pain in the knee following a total knee replacement (TKR) is common in the early postoperative period and is not unexpected.

Correct Answer: D

Rationale: The correct answer is Digitalis. Digitalis is known to cause a flat T wave, depressed ST segment, and a short QT interval on an ECG report. These ECG changes are characteristic of digitalis toxicity. Morphine is not typically associated with these ECG changes. Atropine is more commonly linked to increasing heart rate rather than causing these specific ECG abnormalities. Procardia is a calcium channel blocker that does not typically produce the described ECG findings. Therefore, Digitalis is the most likely medication causing these effects in the patient.