Which of these is not a broad spectrum antibiotic?

(c) Penicillin G

Gram-positive or Gram-negative bacteria are narrow spectrum antibiotics. If effective against a single organism or disease, they are referred to as limited spectrum antibiotics. Penicillin G has a narrow spectrum. Ampicillin and Amoxycillin are synthetic modifications of penicillin. These have broad spectrum. Chloramphenicol. isolated in 1947, is a broad spectrum antibiotic.