51. Amphotericin B and polymyxin interfere with
A. cell wall synthesis
B. protein synthesis
C. cell membrane function
D. DNA function
52. Which of the following is not β-lactamase-resistant penicillin?
A. Oxacillin
B. Nafcillin
C. Carbenicillin
D. Methicillin
53. The antibiotics which afford a broad spectrum of antimicrobial coverage against aerobic and anaerobic bacteria, rickettsiae, chlamydiae, and mycoplasmas is
A. gentamicin
B. tetracycline
C. metronidazole
D. vancomycin