[A] : The signet ring trophozoite of malarial parasite ingests major part of cytoplasm of erythrocytes and form a food vacuole into which it secretes digestive enzymes .
[R] : The enzymes cause breakdown of Haemoglobin into hematin and protein contents .

Options

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

Answer

To solve the question regarding the assertion and reason related to the signet ring trophozoite of the malarial parasite, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that the signet ring trophozoite of the malarial parasite ingests a major part of the cytoplasm of erythrocytes (red blood cells) and forms a food vacuole into which it secretes digestive enzymes.
- This is generally true as the trophozoite stage of the malaria parasite does invade red blood cells and forms a food vacuole.

2. **Understanding the Reason (R)**:
- The reason provided states that the enzymes cause the breakdown of hemoglobin into hematin and protein contents.
- While it is true that the malarial parasite breaks down hemoglobin, the specific statement about the enzymes and their exact products may not be entirely accurate in the context given.

3. **Evaluating the Relationship**:
- The assertion is true, as the trophozoite does ingest cytoplasm and forms a food vacuole.
- The reason is also true, as hemoglobin is broken down, but it does not directly explain the assertion. The enzymes secreted by the trophozoite do not solely account for the breakdown of hemoglobin into hematin and proteins as stated.

4. **Conclusion**:
- Since both the assertion and the reason are true, but the reason does not correctly explain the assertion, the correct answer is that both A and R are true, but R is not a correct explanation of A.

### Final Answer:
Both assertion (A) and reason (R) are true, but R is not a correct explanation of A.

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