Keys are made for the taxonomy of :-

Options

A. Families of plants only
B. Families of animals only
C. Species of plants only
D. Families, genus and species of both plants and animals

Answer

**Step-by-Step Solution:**

1. **Understanding Taxonomy**: Taxonomy is the science of classification of living organisms. It involves categorizing organisms into groups based on shared characteristics.

2. **Role of Keys in Taxonomy**: Keys are tools used in taxonomy to help identify and classify organisms. They provide a systematic approach to distinguishing between different species or groups based on observable traits.

3. **Types of Organisms**: The question presents four options regarding what keys are made for in taxonomy:
- Families of plants only
- Families of animals only
- Species of plants only
- Families, genus, and species of both plants and animals

4. **Identifying the Correct Option**:
- Keys are not limited to just one group (plants or animals) or just one taxonomic level (families or species).
- They can be used for both plants and animals and can identify organisms at various taxonomic levels, including families, genera, and species.

5. **Conclusion**: Based on the understanding that keys are versatile tools in taxonomy used for identifying both plants and animals at multiple taxonomic levels, the correct answer is:
- **D. Families, genus, and species of both plants and animals.**