Which of the following statement is not true?

Options

A. The keys are based on pair of contrasting character called couplet
B. Each statement in the key is called a lead
C. Common taxonomic keys are required for each taxonomic category.
D. Flora contains the actual account of habitat and distribution of plant of a given area.

Answer

To solve the question "Which of the following statement is not true?", we will analyze each of the provided statements one by one.

### Step-by-Step Solution:

1. **Identify the Statements**:
- We have four statements to evaluate. The first step is to clearly list them out for analysis.

2. **Evaluate Each Statement**:
- **Statement 1**: "The keys are based on a pair of contrasting characters called couplet."
- This statement is true. Taxonomical keys are indeed based on contrasting characters known as couplets.

- **Statement 2**: "Each statement in the key is called a lit."
- This statement is also true. Each statement in a taxonomic key is referred to as a 'lit' or a lead.

- **Statement 3**: "Common taxonomic keys are required for each taxonomic category."
- This statement is incorrect. We do not use common taxonomic keys for all categories; instead, separate taxonomic keys are needed for different taxonomic categories.

- **Statement 4**: "Flora contains the actual account of habitat and distribution of plant of a given area."
- This statement is true. Flora provides detailed information about the habitat and distribution of plants in a specific area.

3. **Determine the Incorrect Statement**:
- After evaluating all statements, we find that Statement 3 is the one that is not true.

4. **Conclusion**:
- The statement that is not true is: "Common taxonomic keys are required for each taxonomic category."

### Final Answer:
The statement that is not true is **Statement 3**: "Common taxonomic keys are required for each taxonomic category."

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