A 26-year-old woman in her 37th week of pregnancy tested positive for Group B Strep (GBS). To prevent passing the infection to her newborn, which antibiotic class is appropriate?

Choice A reason: Beta-lactams, such as penicillin or ampicillin, are the first-line therapy for intrapartum prophylaxis against GBS, effectively preventing neonatal infection. Choice B reason: Aminoglycosides are not first-line for GBS prophylaxis and are typically reserved for gram-negative infections. Choice C reason: Sulfonamides are contraindicated in late pregnancy due to risk of neonatal kernicterus and are not effective for GBS prophylaxis. Choice D reason: Fluoroquinolones are not recommended during pregnancy and are not used for GBS prevention.