Assertion. Gold and platinium occur in native state.
Reason. Gold and platinium are not attacked by moisture, oxygen and carbon dioxide of the atmosphere.

Options

A. If both assertion and reason are true, and reason is the true explanation of the assertion.
B. If both assertion and reason are true, but reason is not the true 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 will analyze both the assertion and the reason step by step.

### Step 1: Understanding the Assertion
The assertion states that "Gold and platinum occur in native state."
- **Explanation**: The native state refers to the occurrence of metals in their free or elemental form, rather than in combined forms (like ores). Gold (Au) and platinum (Pt) are known as noble metals due to their low reactivity. They do not readily combine with other elements, which allows them to exist in their native state.

### Step 2: Understanding the Reason
The reason states that "Gold and platinum are not attacked by moisture, oxygen, and carbon dioxide of the atmosphere."
- **Explanation**: This statement is true. Gold and platinum are resistant to corrosion and oxidation. They do not react with moisture, oxygen, or carbon dioxide, which is a characteristic of noble metals. This lack of reactivity contributes to their stability and allows them to remain in their native state.

### Step 3: Analyzing the Relationship
Now, we need to determine if the reason correctly explains the assertion.
- Since gold and platinum are not reactive and do not combine with moisture, oxygen, or carbon dioxide, this explains why they can be found in their native state. Therefore, the reason supports the assertion.

### Conclusion
Both the assertion and the reason are correct, and the reason correctly explains the assertion. Thus, the final answer is:
- **Both assertion and reason are true, and the reason is a correct explanation of the assertion.**

### Final Answer
The correct option is: **Option 1** - Both assertion and reason are true, and the reason is a correct explanation of the assertion.

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