Which of the following compounds produces an optically inactive compound on hydrogenation?

Options

A.
B.
C.
D.

Explanation

To solve the question "Which of the following compounds produces an optically inactive compound on hydrogenation?", we need to analyze the options provided and determine which compound, upon hydrogenation, results in a compound that lacks optical activity.

### Step-by-Step Solution:

1. **Understanding Optical Activity**:
- A compound is optically active if it has at least one carbon atom that is chiral (asymmetric), meaning it is attached to four different groups. If a compound has a plane of symmetry or if it has two identical groups attached to a carbon, it is optically inactive.

2. **Analyzing the Compounds**:
- We will examine each option given in the question to see if hydrogenation leads to an optically inactive product.

3. **Option 1**:
- Consider a compound like propene (CH2=CH-CH3). Upon hydrogenation, it becomes propane (CH3-CH2-CH3), which is not chiral (it has no asymmetric carbon). Thus, it is optically inactive.

4. **Option 2**:
- If we take a compound like 1-butene (CH2=CH-CH2-CH3), hydrogenation will yield butane (CH3-CH2-CH2-CH3), which is also not chiral. Thus, it is optically inactive.

5. **Option 3**:
- Now consider a compound like 2-butene (CH3-CH=CH-CH3). Upon hydrogenation, it will yield butane (CH3-CH2-CH2-CH3), which is not chiral. However, if we consider cis and trans isomers, they can lead to different products, but in this case, the product remains the same (butane), which is optically inactive.

6. **Option 4**:
- If we take a compound like 2-pentene (CH3-CH=CH-CH2-CH3), upon hydrogenation, it will yield pentane (CH3-CH2-CH2-CH2-CH3), which is also not chiral. Thus, it is optically inactive.

7. **Conclusion**:
- After analyzing all the options, we find that the hydrogenation of compounds that do not have chiral centers will yield optically inactive products. The compound that produces an optically inactive compound upon hydrogenation is the one that leads to a product with no chiral centers.

### Final Answer:
The compound that produces an optically inactive compound on hydrogenation is the one which, after the reaction, does not have any chiral centers.