BCG vaccine conatins :-

Options

A. killed mycobacteria
B. live attenuated mycobacteria
C. recombinant protein of mycobacteria
D. antibody against mycobacterai

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the components of the BCG vaccine. BCG stands for Bacillus Calmette-Guérin, which is primarily used to protect against tuberculosis (TB).

2. **Identifying the Options**: The options provided are:
- Killed mycobacteria
- Live attenuated mycobacteria
- Recombinant protein of mycobacteria
- Antibody against mycobacteria

3. **Analyzing the Options**:
- **Killed Mycobacteria**: This option refers to a vaccine made from dead bacteria. The BCG vaccine does not use killed bacteria.
- **Live Attenuated Mycobacteria**: This option refers to a vaccine made from live bacteria that have been weakened so they cannot cause disease. This is the correct description of the BCG vaccine.
- **Recombinant Protein of Mycobacteria**: This option refers to vaccines that use specific proteins from the bacteria, which is not how the BCG vaccine is made.
- **Antibody Against Mycobacteria**: This option refers to a treatment rather than a vaccine component. The BCG vaccine does not contain antibodies.

4. **Conclusion**: Based on the analysis, the BCG vaccine contains live attenuated mycobacteria, specifically a strain of Mycobacterium bovis that has been weakened to stimulate an immune response without causing disease.

5. **Final Answer**: The BCG vaccine contains **live attenuated mycobacteria**.

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