Assertion (A) : Encephalomalacia diseases of poultry is caused by the protozoan Elimeria .
Reason (R) : Eimeria causes bloody diarrhoea in poultry .

Options

A. Both A and R are correct and R is the correct explanation of A
B. Both A and R are correct but R is not the correct explanation of A
C. A is true but R is false
D. A is false and R is true

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**: The assertion states that "Encephalomalacia disease of poultry is caused by the protozoan Eimeria."
- **Analysis**: Encephalomalacia is a neurological condition in poultry characterized by the softening of brain tissues. It is primarily associated with a deficiency of Vitamin E, not caused by any protozoan.

2. **Understanding the Reason (R)**: The reason states that "Eimeria causes bloody diarrhea in poultry."
- **Analysis**: Eimeria is indeed a protozoan that causes coccidiosis in poultry, which is associated with symptoms like bloody diarrhea. This statement is accurate.

3. **Evaluating the Relationship**: Now we need to evaluate the relationship between the assertion and the reason.
- **Assertion Evaluation**: The assertion is false because encephalomalacia is caused by Vitamin E deficiency, not Eimeria.
- **Reason Evaluation**: The reason is true as Eimeria does cause bloody diarrhea in poultry.

4. **Conclusion**: Since the assertion is false and the reason is true, we can conclude that the correct answer is that the assertion is incorrect while the reason is correct.

### Final Answer:
- Assertion (A) is false, and Reason (R) is true. Therefore, the answer is option 4.

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