_________, the most common plastic used by man, is a polymer made from a monomer called ethylene.

Options

A. Ethylene
B. Polythene
C. Ethane
D. Methylene

Explanation

**Step-by-Step Solution:**

1. **Identify the Monomer**: The question states that the plastic is made from a monomer called ethylene. Ethylene is a simple hydrocarbon with the chemical formula C2H4, which can be represented as CH2=CH2.

2. **Understand Polymerization**: The process of forming a polymer from monomers is called polymerization. In this case, when many ethylene molecules (monomers) combine, they undergo polymerization to form a long chain.

3. **Determine the Polymer**: The polymer formed from ethylene is known as polythene (or polyethylene). This is a widely used plastic that is known for its versatility and is commonly found in various products.

4. **Conclude the Answer**: Therefore, the most common plastic used by man, which is a polymer made from the monomer ethylene, is called polythene.

**Final Answer**: Polythene

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