Which of the following groups contain all synthetic substances?

Options

A. Nylon, Terylene, Wool
B. Cotton, Polycot, Rayon
C. PVC, Polythene, Bakelite
D. Acrylic, Silk, Wool

Answer

**Step-by-Step Solution:**

1. **Understand the Definition of Synthetic Substances**: Synthetic substances are materials that are not derived from natural sources. They are man-made and do not originate from plants or animals.

2. **Identify the Groups**: The question presents several groups of substances. We need to analyze each group to determine which contains only synthetic substances.

3. **Analyze Each Group**:
- **Group 1**: Contains nylon, terilene, wool.
- Nylon and terilene are synthetic, but wool is a natural polymer derived from sheep. Therefore, this group is not entirely synthetic.

- **Group 2**: Contains polycot, rayon, cotton.
- Polycot is synthetic, but rayon is derived from natural cellulose, and cotton is a natural fiber from plants. Hence, this group is not entirely synthetic.

- **Group 3**: Contains PVC, polyethylene, and bacillus.
- PVC (Polyvinyl Chloride) and polyethylene are synthetic plastics. Bacillus is a thermosetting plastic, which is also synthetic. This group contains all synthetic substances.

- **Group 4**: Contains acrylic, silk, and wool.
- Acrylic is synthetic, but silk and wool are natural fibers. Therefore, this group is not entirely synthetic.

4. **Conclusion**: After analyzing all the groups, the third group (PVC, polyethylene, and bacillus) contains all synthetic substances.

5. **Final Answer**: The correct option is the third group.

---