Mark the correct statement in the following

Options

A. Injecting microbes during immunization induces passive immunity
B. Cell-mediated immune response is responsible for graft rejection
C. colostrum during initial days of lactation provides active immunity to infant
D. All of these

Answer

To solve the question, we need to analyze each statement provided in the video transcript and determine which one is correct.

### Step-by-Step Solution:

1. **Analyze the First Statement:**
- The first statement claims that "injection microbes during immunization induce passive immunity."
- This statement is incorrect because immunization involves the introduction of antigens (not microbes) to stimulate the body's immune system to produce antibodies. This process leads to active immunity, not passive immunity.

2. **Analyze the Second Statement:**
- The second statement asserts that "cell-mediated immunity response is responsible for graft rejection."
- This statement is correct. Graft rejection is primarily mediated by the immune system's T cells, which are part of cell-mediated immunity. When a foreign tissue (graft) is introduced, the immune system recognizes it as non-self and mounts a response against it.

3. **Analyze the Third Statement:**
- The third statement states that "colostrum during the initial days of lactation provides active immunity to the infant."
- This statement is incorrect. Colostrum, which is the first milk produced after childbirth, contains antibodies (especially IgA) that provide passive immunity to the infant. The infant receives these antibodies directly from the mother, which helps protect against infections.

### Conclusion:
After analyzing all three statements, the correct statement is the second one: "cell-mediated immunity response is responsible for graft rejection."

### Final Answer:
The correct statement is: "Cell-mediated immunity response is responsible for graft rejection."

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