Tick the antibacterial drug – a fluoroquinolone derivative:

Correct Answer: D

Rationale: The correct choice is D: Ciprofloxacin. Ciprofloxacin is a fluoroquinolone derivative known for its broad-spectrum antibacterial activity. It inhibits bacterial DNA gyrase and topoisomerase IV, essential enzymes for DNA replication. This mechanism leads to bacterial cell death. Chloramphenicol (A) inhibits bacterial protein synthesis, Nitrofurantoin (B) disrupts bacterial cell wall synthesis, and Nalidixic acid (C) inhibits bacterial DNA synthesis. Therefore, only Ciprofloxacin (D) targets DNA replication through gyrase inhibition, making it the correct choice.

Correct Answer: B

Rationale: The correct answer is B: Propranolol. Abrupt withdrawal of beta-blockers like propranolol can lead to rebound hypertension and potentially trigger a myocardial infarction (MI) due to sudden increase in heart rate and blood pressure. Aspirin, Lovastatin, and Captopril do not typically cause rebound effects that would lead to a sudden MI upon withdrawal.

Correct Answer: D

Rationale: The correct answer is D: Prazosin. This drug is an alpha-1 adrenergic receptor antagonist commonly used to treat hypertension. The adverse effect described is orthostatic hypotension, which is a known side effect of alpha-1 blockers like prazosin. When prazosin blocks alpha-1 receptors in blood vessels, it can lead to a sudden drop in blood pressure upon standing up, causing orthostatic hypotension. Propranolol (A) is a beta-blocker, Minoxidil (B) is a vasodilator, and Hydralazine (C) is also a vasodilator, but these drugs do not directly affect alpha-1 receptors and are less likely to cause orthostatic hypotension compared to prazosin.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: D

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.