Kelly’s medium is used in the isolation of ?
**Core Concept**
Kelly's medium is a selective growth medium used in microbiology for the isolation and cultivation of specific types of bacteria. It is designed to inhibit the growth of certain bacteria while allowing others to thrive, making it a valuable tool in the identification and characterization of microorganisms.
**Why the Correct Answer is Right**
Kelly's medium is particularly useful for the isolation of Corynebacterium diphtheriae, the bacterium responsible for diphtheria. The medium contains ingredients that selectively inhibit the growth of other bacteria while allowing Corynebacterium diphtheriae to grow. The medium's composition also allows for the production of the toxin responsible for the disease.
**Why Each Wrong Option is Incorrect**
**Option A:** Not applicable - no information is provided about this option.
**Option B:** Blood agar is a general-purpose medium used for the cultivation of a wide range of bacteria, but it is not selective for Corynebacterium diphtheriae.
**Option C:** MacConkey agar is a selective medium used for the isolation of Gram-negative bacteria, but it is not used for Corynebacterium diphtheriae.
**Clinical Pearl / High-Yield Fact**
Kelly's medium is an example of a selective growth medium, which is a crucial tool in the identification and characterization of microorganisms in clinical microbiology.
**Correct Answer:** C. Corynebacterium diphtheriae