Assertion : The basic difference between various types of electromagnetic waves lies in their wavelength or frequencies
Reason : Electromagnetic waves travel through vacuum with the same speed.

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 the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step 1: Understanding the Assertion
The assertion states: "The basic difference between various types of electromagnetic waves lies in their wavelength or frequencies."

- **Analysis**: Electromagnetic waves encompass a wide range of types, including radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. The primary characteristic that differentiates these types is indeed their wavelength (λ) and frequency (ν). The relationship between wavelength and frequency is given by the equation:

\[ c = \lambda \nu \]

where \(c\) is the speed of light. Thus, the assertion is **true**.

### Step 2: Understanding the Reason
The reason states: "Electromagnetic waves travel through vacuum with the same speed."

- **Analysis**: It is a well-established fact in physics that all electromagnetic waves travel at the speed of light in a vacuum, which is approximately \(3 \times 10^8\) meters per second. This statement is also **true**.

### Step 3: Evaluating the Relationship
Now we need to determine if the reason is a correct explanation of the assertion.

- **Analysis**: Since all electromagnetic waves travel at the same speed in a vacuum, the only distinguishing factors between them are their wavelengths and frequencies. Therefore, the reason provided does indeed explain why the assertion is true.

### Conclusion
Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the answer is:

**Option A: Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.**

---