Two statements are given - one labelled Assertion (A) and the other labelled Reason (R). Read the statements carefully and choose the option that correctly describes statements A and R.
Assertion (A): Stars would not twinkle if we viewed them from the moon.
Reason (R): Stars appear to twinkle due to atmospheric refraction of starlight.

Options

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

Answer

To solve the question, we need to analyze both the Assertion (A) and the Reason (R) given in the problem.

### Step 1: Understand the Assertion (A)
The assertion states: "Stars would not twinkle if we viewed them from the moon."
- This statement implies that the twinkling of stars is influenced by the environment from which they are observed.

### Step 2: Understand the Reason (R)
The reason states: "Stars appear to twinkle due to atmospheric refraction of starlight."
- This statement explains the phenomenon of twinkling stars, which occurs because the light from stars is refracted (bent) as it passes through the Earth's atmosphere. The varying density of the atmosphere causes the light to change direction slightly, making the stars appear to twinkle.

### Step 3: Analyze the Relationship Between A and R
- Since the assertion (A) claims that stars would not twinkle from the moon, and the reason (R) correctly explains that the twinkling is due to atmospheric refraction, we can conclude that:
- Both statements are true.
- The reason (R) provides a correct explanation for the assertion (A).

### Conclusion
Based on the analysis:
- Both A and R are true, and R is the correct explanation for A.

### Final Answer
The correct option is: **Both A and R are true and R is the correct explanation for A.**

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