Question

A certain antibiotic X is effective only against a few types of harmful microbes and cells. Which type of antibiotic X is ?.

• A. limited spectrum
• B. antibacterial
• C. broad-spectrum
• D. narrow-spectrum

Answer 1

The correct option is D narrow-spectrum

Antibiotics are classified based on the range of microbes that are affected by it.

The range of bacteria or other microorganisms that are affected by a certain antibiotic is expressed as its spectrum of action. Antibiotics which kill or inhibit a wide range of Gram-positive and Gram-negative bacteria are said to be broad spectrum antibiotics. Those effective mainly against 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 is an example of narrow-spectrum.