Autoimmunity is caused due to the
A. ability of Immune cells to discriminate between self cells from nonself cells.
B. inability of immune cells in damaging self cells representing foreign antigens.
C. inability of immune cells in distinguishing self cells from non-cells
D. ability of immune cells to damage self cells.

Options

A. C and D are correct
B. A,B and C are correct
C. A,B and D are correct
D. None of these

Answer

To solve the question regarding the cause of autoimmunity, we need to analyze the options provided and understand the concept of autoimmunity.

### Step-by-Step Solution:

1. **Understanding Autoimmunity**:
- Autoimmunity occurs when the immune system mistakenly attacks the body's own cells, tissues, or organs. This happens when the immune system loses its ability to distinguish between self (the body’s own cells) and non-self (foreign invaders like pathogens).

2. **Analyzing the Options**:
- **Option A**: "Ability of Immune cells to discriminate between self cells from nonself cells."
- This statement describes a normal function of the immune system. Autoimmunity occurs when this ability is lost, so this option is incorrect.

- **Option B**: "Inability of immune cells in damaging self cells representing foreign antigens."
- This option is somewhat misleading. Autoimmunity is not about the inability to damage self-cells; rather, it is about the immune system mistakenly attacking self-cells as if they were foreign. Therefore, this option is incorrect.

- **Option C**: "Inability of immune cells in distinguishing self cells from non-cells."
- This option correctly describes a key aspect of autoimmunity. When immune cells cannot distinguish between self and non-self, they may attack the body’s own cells. Thus, this option is correct.

- **Option D**: "Ability of immune cells to damage self cells."
- This option also correctly describes a characteristic of autoimmunity. In autoimmune disorders, the immune system actively damages self-cells. Therefore, this option is also correct.

3. **Conclusion**:
- The correct answers are **Option C** and **Option D**. Autoimmunity is caused by the inability of immune cells to distinguish self from non-self (Option C) and the ability of immune cells to damage self-cells (Option D).

### Final Answer:
The correct options are **C and D**.

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