Assertion Arteries possess smooth muslces on their walls.
Reason These smooth muscles help in regulating blood volume flowing through a tissue of organ.

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

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Arteries possess smooth muscles on their walls."
- This is true. Arteries have a layer of smooth muscle in their walls that allows them to be flexible and able to withstand high pressure from the blood being pumped by the heart.

2. **Understanding the Reason**:
- The reason given is "These smooth muscles help in regulating blood volume flowing through a tissue or organ."
- This statement is also true. The smooth muscles in the walls of arteries can contract or relax, which helps to regulate the diameter of the blood vessels. This regulation affects the amount of blood that flows to different tissues and organs.

3. **Relationship Between Assertion and Reason**:
- The reason explains how the smooth muscles in arteries function. When these muscles contract, they narrow the artery (vasoconstriction), which decreases blood flow to a particular area. Conversely, when they relax (vasodilation), the artery widens, allowing more blood to flow.
- Therefore, the reason provides a correct explanation for the assertion.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Thus, the answer is that both the assertion and reason are true, and the reason is the correct explanation for the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is the correct explanation of the assertion.

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