Assertion (A): Plasmodium, a protozoan parasite initially multiplies in liver cells and enters blood cells.
Reason (R): It is responsible for the cause of filariasis.

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**:
- The assertion states that "Plasmodium, a protozoan parasite initially multiplies in liver cells and enters blood cells."
- This is true. Plasmodium is known to infect the liver cells first before entering the bloodstream and infecting red blood cells (RBCs).

2. **Understanding the Reason (R)**:
- The reason states that "It is responsible for the cause of filariasis."
- This is false. Filariasis is caused by filarial worms, not by Plasmodium. The disease caused by Plasmodium is malaria.

3. **Conclusion**:
- Since the assertion is true and the reason is false, we can conclude that the assertion is correct, but the reason is incorrect.

4. **Final Answer**:
- The correct option is that the assertion is true and the reason is false.

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