Assertion In electromagnetic wave, if direction of veriations of electric and magnetic field are perpendicular to each other and also perpendicular to the direction of wave propagation.
Reason Electronegative waves are transverse in nature.

Options

A. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
B. If both Assertion and Reason are true but Reason is not correct explanation of Assertion.
C. If Assertion is true but Reason is false.
D. If Assertion is false but Reason is true.

Explanation

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states that in an electromagnetic wave, the directions of the variations of the electric field (E) and the magnetic field (B) are perpendicular to each other and also perpendicular to the direction of wave propagation.

**Explanation:**
- In electromagnetic waves, the electric field and magnetic field oscillate in planes that are perpendicular to each other.
- For example, if the electric field oscillates in the x-direction, the magnetic field will oscillate in the y-direction, while the wave itself propagates in the z-direction.

### Step 2: Understand the Reason
The reason states that electromagnetic waves are transverse in nature.

**Explanation:**
- A transverse wave is defined as a wave in which the oscillations are perpendicular to the direction of wave propagation.
- Since the electric and magnetic fields in an electromagnetic wave are perpendicular to the direction of propagation, this confirms that electromagnetic waves are indeed transverse waves.

### Step 3: Conclusion
Both the assertion and the reason are true. The reason correctly explains the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is a correct explanation of the assertion.

### Final Answer:
Both the assertion and reason are true, and the reason is a correct explanation of the assertion.

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