Assertion : Ethene can be catalytically hydrogenated.
Reason : Ethene contains all C-H bonds.

Explanation

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

### Step 1: Analyze the Assertion
The assertion states that "Ethene can be catalytically hydrogenated."

- Ethene (C₂H₄) is an alkene that contains a carbon-carbon double bond (C=C).
- Catalytic hydrogenation is a reaction where hydrogen (H₂) is added across the double bond in the presence of a catalyst (such as palladium, platinum, or nickel).
- When ethene undergoes catalytic hydrogenation, the double bond is converted into a single bond, resulting in ethane (C₂H₆).

**Conclusion for Step 1:** The assertion is correct because ethene can indeed be hydrogenated.

### Step 2: Analyze the Reason
The reason states that "Ethene contains all C-H bonds."

- Ethene has the molecular formula C₂H₄, which means it has two carbon atoms and four hydrogen atoms.
- However, it contains a double bond between the carbon atoms (C=C), which means not all bonds in ethene are C-H bonds. The double bond is a C=C bond, not a C-H bond.

**Conclusion for Step 2:** The reason is incorrect because ethene does not contain only C-H bonds; it also contains a C=C double bond.

### Step 3: Final Conclusion
Based on the analysis:
- The assertion is true: Ethene can be catalytically hydrogenated.
- The reason is false: Ethene does not contain all C-H bonds.

Thus, the correct answer to the question is that the assertion is true but the reason is false.

### Final Answer:
The correct option would be C (Assertion is true, Reason is false).

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