A: The electrical. Conductivity of the Earth's atmosphere does not change with altitude.
R : Cosmic rays from outer space entering the earth's atmosphere do not affect it.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To analyze the statements given in the question, we will break down the assertion (A) and the reason (R) step by step.

### Step 1: Understand the Assertion
The assertion states: "The electrical conductivity of the Earth's atmosphere does not change with altitude."

- **Analysis**: The electrical conductivity of a medium is influenced by its composition and density. As altitude increases, the composition of the atmosphere changes (e.g., the proportion of gases like oxygen and nitrogen decreases). This change in composition affects the medium's properties, including its electrical conductivity.

### Step 2: Evaluate the Assertion
Since the composition of the atmosphere changes with altitude, it implies that the electrical conductivity will also change. Therefore, the assertion is **false**.

### Step 3: Understand the Reason
The reason states: "Cosmic rays from outer space entering the Earth's atmosphere do not affect it."

- **Analysis**: Cosmic rays are high-energy particles that can interact with the Earth's atmosphere. When they enter the atmosphere, they can ionize atoms and molecules, which can lead to changes in the electrical properties of the atmosphere, including its conductivity.

### Step 4: Evaluate the Reason
Since cosmic rays do affect the Earth's atmosphere by ionizing particles and altering its conductivity, the reason is also **false**.

### Conclusion
Both the assertion (A) and the reason (R) are false statements. Therefore, the correct answer is that both statements are incorrect.

### Final Answer
Both the assertion and the reason are false.

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