`GRA`is a copolymer of:

Options

A. Butadiene and acrylonitrile
B. Butadiene and adipic acid
C. Chloroprene and acrylonitrile
D. Chloroprene and adipic acid

Answer

To determine which monomers form the copolymer GRA, we need to analyze the options provided and identify the correct pair of monomers.

### Step-by-Step Solution:

1. **Understand the Definition of Copolymer**: A copolymer is a polymer that is made from two different types of monomers.

2. **Identify the Given Options**: The options provided are:
- A) Butadiene and Acrylonitrile
- B) Butadiene and Adipic Acid
- C) Chloroprene and Acrylonitrile
- D) Chloroprene and Adipic Acid

3. **Recall the Composition of GRA**: The question states that GRA is a copolymer. We need to identify which of the options corresponds to a known copolymer.

4. **Recognize the Known Copolymer**:
- The copolymer commonly known as Buna-N is made from 1,3-butadiene and acrylonitrile.
- Therefore, the correct pair of monomers that forms the copolymer GRA is Butadiene and Acrylonitrile.

5. **Conclusion**: Based on the analysis, the correct answer is:
- **Option A: Butadiene and Acrylonitrile**.

### Final Answer:
GRA is a copolymer of **Butadiene and Acrylonitrile**.

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