Vicinal dihalide is

Options

A. `CH_3CH_2Br`
B. `BrCH_2CH_2Br`
C. `CH_3CHBr_2`
D. `CH_2=CHBr`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Terms:**
- The term "di" in chemistry refers to the presence of two identical or different groups attached to a molecule.
- "Halide" refers to a halogen atom (fluorine, chlorine, bromine, iodine) that is bonded to a carbon atom in an organic compound.

2. **Defining Vicinal:**
- The term "vicinal" refers to the relative positions of substituents on a carbon chain. Specifically, vicinal dihalides have two halogen atoms attached to adjacent carbon atoms in a chain.

3. **Identifying Vicinal Dihalides:**
- A vicinal dihalide can be represented as R-CH(X)-CH(Y)-R', where X and Y are halogen atoms (e.g., Cl, Br, I) and R and R' can be hydrogen or alkyl groups.
- For example, if we take 1,2-dichloroethane (Cl-CH2-CHCl2), it is a vicinal dihalide because the two chlorine atoms are attached to adjacent carbon atoms.

4. **Examples of Vicinal Dihalides:**
- 1,2-dichloroethane (Cl-CH2-CHCl)
- 1,2-dibromoethane (Br-CH2-CHBr)
- 1,2-difluoroethane (F-CH2-CHF)

5. **Conclusion:**
- In summary, a vicinal dihalide is a compound that contains two halogen atoms attached to adjacent carbon atoms in a carbon chain.

---