DNA sequence is the basis of grouping organisms in

Options

A. Karyotaxonomy
B. Cytotaxonomy
C. Phenetics
D. Chemotaxonomy

Answer

To solve the question "DNA sequence is the basis of grouping organisms in," we will analyze the provided options and determine which one is most closely related to DNA sequencing.

### Step-by-Step Solution:

1. **Understand the Options**: The options given are karyotaxonomy, cytotaxonomy, fanatics, and chemotaxonomy. We need to understand what each term means in relation to DNA sequencing.

2. **Define Karyotaxonomy**: Karyotaxonomy is the classification of organisms based on the structure and number of chromosomes. It focuses on chromosomal characteristics like size, shape, and number, but does not specifically involve DNA sequencing.

3. **Define Cytotaxonomy**: Cytotaxonomy involves the classification of organisms based on cellular structures. While it may consider genetic information, it does not primarily focus on DNA sequences.

4. **Define Fanatics**: Fanatics (or phenetics) classifies organisms based on overall similarity, usually in terms of morphological traits. This approach does not involve DNA sequencing.

5. **Define Chemotaxonomy**: Chemotaxonomy is the classification of organisms based on their chemical and biochemical composition. This includes the study of nucleic acids (DNA and RNA), amino acids, and other biochemical markers. Since DNA sequencing directly relates to the analysis of nucleic acids, this option is relevant.

6. **Conclusion**: After analyzing all the options, we find that chemotaxonomy is the classification method that utilizes DNA sequences as a basis for grouping organisms. Therefore, the correct answer is chemotaxonomy.

### Final Answer:
The DNA sequence is the basis of grouping organisms in **chemotaxonomy**.

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