Assertion : The failure of secretion of hormone vasopressin causes diabetes mellitus in the patient.
Reason : Vasopression reduces the volume of urine by increasing the reabsorbtion of water from the urine.

Options

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

Answer

To solve the assertion-reason question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states: "The failure of secretion of hormone vasopressin causes diabetes mellitus in the patient."

- **Understanding Vasopressin**: Vasopressin, also known as antidiuretic hormone (ADH), is primarily involved in regulating water balance in the body.
- **Diabetes Mellitus vs. Diabetes Insipidus**: Diabetes mellitus is characterized by high blood sugar levels due to insulin deficiency or resistance. On the other hand, diabetes insipidus is a condition that arises when there is insufficient secretion of vasopressin, leading to excessive urination and thirst.

**Conclusion**: The assertion is false because the failure of vasopressin secretion leads to diabetes insipidus, not diabetes mellitus.

### Step 2: Analyze the Reason
The reason states: "Vasopressin reduces the volume of urine by increasing the reabsorption of water from the urine."

- **Function of Vasopressin**: This statement accurately describes the function of vasopressin. It acts on the kidneys to promote water reabsorption, thus reducing urine volume.

**Conclusion**: The reason is true.

### Step 3: Determine the Relationship
Now we need to determine the relationship between the assertion and the reason:

- The assertion is false, and the reason is true. Therefore, the reason does not support the assertion.

### Final Conclusion
Both the assertion and the reason are not correct in their relationship. The correct answer choice would be the one that states both the assertion and the reason are false.

### Answer:
The correct answer is (D) Both assertion and reason are false.

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