A taxonomic key used to identify organisms is labeled:

Options

A. phylogenetic key
B. evergreen key
C. dichotomous key
D. none of the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about a taxonomic key used to identify organisms and what it is labeled as.

2. **Defining a Taxonomic Key**: A taxonomic key is a tool that helps in identifying organisms based on their characteristics. It provides a systematic way to classify and identify species.

3. **Identifying the Type of Key**: The specific type of taxonomic key being referred to in the question is the "dichotomous key."

4. **Meaning of Dichotomous**: The term "dichotomous" comes from the Greek word "dichotomos," which means "divided in two." This indicates that the key works by offering two contrasting choices at each step.

5. **Function of a Dichotomous Key**: As you move through the dichotomous key, you make choices based on the characteristics of the organism you are trying to identify. Each choice leads you closer to the identification of the organism.

6. **Conclusion**: Therefore, the answer to the question is that a taxonomic key used to identify organisms is labeled as a "dichotomous key."

### Final Answer:
A taxonomic key used to identify organisms is labeled as a **dichotomous key**.

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