Mark the odd one in the following.

Options

A. Family
B. Cohort
C. Taxon
D. Species

Explanation

To solve the question "Mark the odd one in the following," we need to analyze the given options: family, cohort, taxon, and species.

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Family**: This is a rank in the hierarchical classification of organisms. It is a category that groups together related organisms.
- **Cohort**: This is also a rank in the classification hierarchy, situated between subclass and superorder. It is considered a category.
- **Taxon**: This term refers to a named group of organisms that can be of any rank. It is a broader term that encompasses various categories.
- **Species**: This is the most specific rank in classification, referring to a group of organisms that can interbreed and produce fertile offspring. It is a category as well.

2. **Identify Categories vs. Taxon**:
- Family, cohort, and species are all specific ranks or categories in the taxonomy hierarchy.
- Taxon, on the other hand, is a general term that refers to any group of organisms, regardless of the rank.

3. **Determine the Odd One Out**:
- Since family, cohort, and species are all specific categories in the classification system, while taxon is a general term that can refer to any group of organisms, the odd one out is **taxon**.

### Final Answer:
The odd one in the following options is **taxon**.

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