Group of related species is called _________ .

Options

A. genus
B. family
C. order
D. class

Explanation

**Step-by-Step Solution:**

1. **Understanding Classification**: The classification of living organisms is hierarchical and starts from the broadest category (kingdom) down to the most specific (species).

2. **Identifying the Levels of Classification**: The levels of classification in order are:
- Kingdom
- Phylum
- Class
- Order
- Genus
- Species

3. **Focusing on Related Species**: The question asks for the term that describes a group of related species. In the classification hierarchy, the level that groups species together is the genus.

4. **Example for Clarity**: For instance, humans belong to the following classifications:
- Kingdom: Animalia
- Phylum: Chordata
- Class: Mammalia
- Order: Primates
- Genus: Homo
- Species: Homo sapiens

5. **Conclusion**: From the explanation and the example, we can conclude that the group of related species is called a **genus**.

**Final Answer**: Group of related species is called **genus**.

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