Which is the odd one in the following series ?

Options

A. sapiens
B. americana
C. rotundus
D. Hemidactylus

Explanation

To solve the question "Which is the odd one in the following series?" with the options provided (sapiens, americana, rotundus, and hemidactyls), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Names**:
- The first step is to identify what each of the names represents.
- "sapiens" refers to *Homo sapiens*, the species name for humans.
- "americana" refers to *Periplaneta americana*, the species name for the American cockroach.
- "rotundus" refers to *Cyperus rotundus*, the species name for a type of plant.
- "hemidactyls" refers to *Hemidactylus*, which is the genus name for a group of lizards known as house geckos.

2. **Classify the Names**:
- Next, we classify each name based on whether it is a species name or a genus name.
- "sapiens" is a species name.
- "americana" is a species name.
- "rotundus" is a species name.
- "hemidactyls" is a genus name.

3. **Determine the Odd One Out**:
- After classifying the names, we can see that the first three names (sapiens, americana, and rotundus) are species names, while "hemidactyls" is a genus name.
- Therefore, "hemidactyls" is the odd one out in this series.

4. **Conclusion**:
- The odd one in the series is "hemidactyls" because it is a genus name, while the others are species names.

### Final Answer:
The correct option is **hemidactyls**.

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