(A ): The tails of comets are always oriented in a direction away from Sun (R) : Electromagentic waves exert pressure.

Options

A. Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.
B. Both 'A' and ’R' are true and 'R' is not the correct explanation of 'A
C. A' is true and 'R' is false
D. 'A' is false and R' is true

Answer

To solve the question, we need to analyze the assertion and reason provided and determine their validity.

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "The tails of comets are always oriented in a direction away from the Sun."
- This statement is true. The tails of comets do indeed point away from the Sun due to the solar wind and radiation pressure.

2. **Understanding the Reason (R)**:
- The reason states that "Electromagnetic waves exert pressure."
- This statement is also true. Electromagnetic waves, such as those emitted by the Sun, can exert pressure on objects, including the gas and dust particles in a comet's tail.

3. **Connecting Assertion and Reason**:
- The reason explains why the assertion is true. The pressure exerted by the Sun's electromagnetic waves (solar radiation) pushes the particles in the comet's coma (the cloud of gas and dust surrounding the comet) away from the Sun, causing the tail to point away from it.

4. **Conclusion**:
- Since both the assertion and reason are true, and the reason correctly explains the assertion, we can conclude that the correct answer is that both A and R are true, and R is the correct explanation of A.

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

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