Vinyl bromide undergoes :

Options

A. Addition reaction
B. Substitution reaction
C. Elimination reaction
D. Rearrangement reaction

Explanation

To determine the reactions that vinyl bromide (CH2=CHBr) can undergo, we will analyze each of the four types of reactions: addition, substitution, elimination, and rearrangement.

### Step-by-Step Solution:

1. **Identify the Structure of Vinyl Bromide:**
- Vinyl bromide has the structure CH2=CHBr, which indicates it is an alkene due to the presence of a double bond between the two carbon atoms.

2. **Addition Reaction:**
- Vinyl bromide can undergo addition reactions. For example, when it reacts with hydrogen in the presence of a platinum catalyst, it adds across the double bond to form ethyl bromide (CH3CH2Br).
- **Conclusion:** Vinyl bromide undergoes addition reactions.

3. **Substitution Reaction:**
- In a substitution reaction, we would expect a nucleophile to replace the bromine atom. However, if vinyl bromide were to undergo an SN1 substitution, it would form a vinyl cation (CH2=CH+), which is unstable due to the sp-hybridized carbon's inability to stabilize the positive charge effectively.
- **Conclusion:** Vinyl bromide does not undergo substitution reactions.

4. **Elimination Reaction:**
- Vinyl bromide can also undergo elimination reactions. For instance, it can lose HBr to form acetylene (C2H2) through an elimination mechanism.
- **Conclusion:** Vinyl bromide undergoes elimination reactions.

5. **Rearrangement Reaction:**
- Rearrangement reactions typically involve the reorganization of the molecular structure to form a different isomer. However, vinyl bromide has only two carbon atoms, and there is no possibility for a rearrangement that would yield a different structure.
- **Conclusion:** Vinyl bromide does not undergo rearrangement reactions.

### Final Summary:
- Vinyl bromide undergoes **addition** and **elimination** reactions.
- It does not undergo **substitution** or **rearrangement** reactions.