Assertion: For biological functions in human body, barium is not required.
Reason: Barium is a divalent ion.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason 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

To analyze the given assertion and reason, we will break down the statement step by step.

### Step 1: Understanding the Assertion
The assertion states that "For biological functions in the human body, barium is not required."

- **Explanation**: In biological systems, certain elements are essential for various functions. Commonly required ions include sodium (Na⁺), potassium (K⁺), calcium (Ca²⁺), and magnesium (Mg²⁺). Barium (Ba²⁺) is not one of these essential ions. In fact, barium can be toxic in high concentrations and does not play a known role in human biological functions.

### Step 2: Understanding the Reason
The reason provided is "Barium is a divalent ion."

- **Explanation**: Barium is indeed a divalent ion, meaning it has a +2 charge (Ba²⁺). While it is true that many biological functions involve divalent ions (like calcium and magnesium), the mere fact that barium is a divalent ion does not imply that it is necessary for biological functions.

### Step 3: Evaluating the Relationship Between Assertion and Reason
Now, we need to determine if the reason correctly explains the assertion.

- **Analysis**: The assertion is true (barium is not required for biological functions), but the reason does not provide a valid explanation for this assertion. Just because barium is a divalent ion does not mean it is required or beneficial in biological systems.

### Conclusion
- The assertion is true: Barium is not required for biological functions in the human body.
- The reason is also true: Barium is a divalent ion.
- However, the reason does not correctly explain the assertion.

### Final Answer
Both the assertion and the reason are true, but the reason is not a correct explanation of the assertion.

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