Synthetic fibres are made up of large molecules known as______

Options

A. Polymers
B. Monomers
C. Petrochemicals
D. Hydrocarbons

Explanation

**Step-by-Step Solution:**

1. **Understanding Synthetic Fibres**: Synthetic fibres are materials created through chemical processes, often derived from petrochemicals. They are not natural but are manufactured.

2. **Identifying the Composition**: The question asks what synthetic fibres are made up of. To answer this, we need to consider the structure of these fibres.

3. **Defining Large Molecules**: In chemistry, large molecules are often referred to as polymers. Polymers are made up of repeating units called monomers.

4. **Eliminating Incorrect Options**:
- **Monomers**: These are the small units that make up polymers, not the large molecules themselves.
- **Petrochemicals**: While synthetic fibres may be derived from petrochemicals, they are not the large molecules that constitute the fibres.
- **Hydrocarbons**: These are organic compounds made of hydrogen and carbon, but they do not specifically refer to the large molecules in synthetic fibres.

5. **Conclusion**: Since synthetic fibres are composed of large molecules known as polymers, the correct answer is "polymers".

**Final Answer**: Synthetic fibres are made up of large molecules known as **polymers**.

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