Assertion (A): Noble gases are highly reactive.
Reason (R): Noble gases have stable closed shell electronic configuration.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A.
C. A is true but R is false.
D. A is false and R is true.

Explanation

To solve the question regarding the assertion and reason about noble gases, we can break it down into clear steps:

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**: The assertion states that "Noble gases are highly reactive." We need to determine whether this statement is true or false.

2. **Understanding the Reason (R)**: The reason states that "Noble gases have stable closed shell electronic configuration." We need to evaluate the truth of this statement as well.

3. **Evaluating the Assertion**: Noble gases, which are found in Group 18 of the periodic table (such as Helium, Neon, Argon, Krypton, Xenon, and Radon), are known for their lack of reactivity. They have a complete valence shell, which makes them very stable and unreactive. Therefore, the assertion that noble gases are highly reactive is **false**.

4. **Evaluating the Reason**: The reason states that noble gases have a stable closed shell electronic configuration. This is true because noble gases have a full outer shell of electrons (ns²np⁶ configuration), which contributes to their stability and lack of reactivity.

5. **Conclusion**: Since the assertion (A) is false and the reason (R) is true, we can conclude that the correct relationship is that A is false and R is true.

### Final Answer:
- Assertion (A) is false.
- Reason (R) is true.
- Therefore, the correct option is that A is false but R is true.

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