Jeweller's weights are obtained from

Options

A. Sesbania grandiflora
B. Abrus precatorius
C. Psoralea corylifolia
D. Cyamopsis tetragonaloba.

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the source of jeweller's weights.

2. **Review the Options**: The options provided include various plant species. We need to determine which plant's seeds are used for jeweller's weights.

3. **Recognize the Correct Plant**: The jeweller's weights are derived from the seeds of the **Abrus precatorius**, commonly known as crab eye seed or rosary pea.

4. **Understand the Characteristics of Abrus precatorius**:
- It is a herbaceous flowering plant belonging to the legume family (Fabaceae).
- It is a perennial climber with long, pinnate leaves that can twist around trees, shrubs, and hedges.
- The seeds are brightly colored, which makes them visually appealing for use in jewelry.

5. **Confirm the Usage of the Seeds**: The seeds of Abrus precatorius are specifically valued for their bright coloration and have historically been used to weigh gold, confirming their role as jeweller's weights.

6. **Evaluate Other Options**:
- **Sesbania grandiflora**: Known for its edible leaves and flowers, not used for jeweller's weights.
- **Sorghum halepense**: Used in traditional medicine, not for jeweller's weights.
- **Cymopsis tetragonoloba**: Known as guar or cluster bean, also not used for jeweller's weights.

7. **Conclusion**: Based on the information gathered, the correct answer is that jeweller's weights are obtained from **Abrus precatorius**.

**Final Answer**: Jeweller's weights are obtained from **Abrus precatorius**.

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