Assertion: Malpighian tubules are excretory organs in most of the insects.
Reason: These help in excretion of urea and creatinine.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reson are true but reason is not the correct explanation of assertion.
C. if assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Malpighian tubules are excretory organs in most of the insects." This is true. Malpighian tubules are indeed the primary excretory structures found in many insects, functioning similarly to kidneys in vertebrates.

2. **Understanding the Reason**: The reason states that "These help in excretion of urea and creatinine." This is false. Insects primarily excrete nitrogenous waste in the form of uric acid, not urea or creatinine. Uric acid is excreted as a semi-solid paste, which helps in conserving water.

3. **Evaluating the Assertion and Reason**: Since the assertion is true and the reason is false, we conclude that the assertion stands correct on its own while the reason does not support it.

4. **Final Conclusion**: Therefore, the correct answer is that the assertion is true, but the reason is false.

**Answer**: Option C (Assertion is true, Reason is false).

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