`C_4H_9X` is a

Options

A. Pri-alkyl halide
B. sec -alkyl halide
C. Tert-alkyl halide
D. Primary , sec or tertiary alkyl halide

Explanation

To determine whether `C4H9X` can be classified as a primary, secondary, or tertiary alkyl halide, we need to analyze the structure of the compound based on its molecular formula.

### Step-by-Step Solution:

1. **Identify the Molecular Formula:**
The given molecular formula is `C4H9X`, where `X` represents a halogen atom (like Cl, Br, I, or F).

2. **Understand Alkyl Halides:**
- **Primary Alkyl Halide:** The carbon atom bonded to the halogen is attached to only one other carbon atom (one alkyl group).
- **Secondary Alkyl Halide:** The carbon atom bonded to the halogen is attached to two other carbon atoms (two alkyl groups).
- **Tertiary Alkyl Halide:** The carbon atom bonded to the halogen is attached to three other carbon atoms (three alkyl groups).

3. **Construct Possible Structures:**
- **Primary Alkyl Halide:**
- Structure: CH3-CH2-CH2-CH2-X (Halogen attached to the terminal carbon)
- Here, the halogen is attached to a carbon that is connected to only one other carbon.
- **Secondary Alkyl Halide:**
- Structure: CH3-CH2-CH(X)-CH3 (Halogen attached to a carbon that is connected to two other carbons)
- In this case, the halogen is attached to the second carbon in the chain.
- **Tertiary Alkyl Halide:**
- Structure: CH3-C(X)(CH3)-CH2-CH3 (Halogen attached to a carbon that is connected to three other carbons)
- Here, the halogen is attached to a carbon that is connected to three other carbons.

4. **Count the Carbon Atoms:**
- In all cases, we have a total of four carbon atoms (`C4`), which allows for the formation of primary, secondary, and tertiary alkyl halides.

5. **Conclusion:**
Since we can construct structures for primary, secondary, and tertiary alkyl halides using the formula `C4H9X`, we conclude that `C4H9X` can be classified as a primary alkyl halide, a secondary alkyl halide, or a tertiary alkyl halide depending on the specific structure formed.

### Final Answer:
`C4H9X` can be a primary alkyl halide, a secondary alkyl halide, or a tertiary alkyl halide.