Assertion: It is essential that all the lines available in the emission spectrum will also be available in the absorption spectrum.
Reason: The spectrum of hydrogen atom is only absorption spectrum.

Options

A. If both assertion and reason are ture 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 reson are false.

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states: "It is essential that all the lines available in the emission spectrum will also be available in the absorption spectrum."

- **Explanation**: The emission spectrum of an atom consists of the wavelengths of light emitted when electrons transition from higher energy levels to lower energy levels. The absorption spectrum, on the other hand, consists of the wavelengths absorbed by electrons when they transition from lower energy levels to higher energy levels. Therefore, the wavelengths that appear in the emission spectrum will correspond to the wavelengths that can be absorbed, making the assertion true.

### Step 2: Understand the Reason
The reason states: "The spectrum of hydrogen atom is only absorption spectrum."

- **Explanation**: This statement is incorrect. The hydrogen atom exhibits both an emission spectrum and an absorption spectrum. The emission spectrum is produced when electrons fall to lower energy levels, while the absorption spectrum occurs when electrons absorb energy and move to higher energy levels. Therefore, the reason is false.

### Step 3: Conclusion
Based on the analysis:
- The assertion is true.
- The reason is false.

Thus, the correct option is that the assertion is true, but the reason is false.

### Final Answer
The correct option is **C**: Assertion is true but reason is false.

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