The term 'systematics' refers to

Options

A. identification and study of organ systems
B. identification and preservation of plants and animals
C. diversity of kinds of organisms and their relationship
D. study of habitats of organisms and their classification.

Explanation

To answer the question "The term 'systematics' refers to," we will analyze the provided options step by step.

### Step 1: Understand the Definition of Systematics
Systematics is a branch of biology that focuses on the classification and organization of living organisms. It involves studying the diversity of organisms and their evolutionary relationships.

### Step 2: Evaluate Each Option
1. **Identification and study of organ systems**: This option pertains to anatomy and physiology, not systematics.

2. **Identification and preservation of plants and animals**: While this involves aspects of biology, it does not specifically define systematics.

3. **Diversity of kinds of organisms and their relationship**: This option aligns with the definition of systematics, as it encompasses both the variety of organisms and their evolutionary connections.

4. **The study of habitats of organisms and their classification**: This option relates more to ecology and biogeography rather than systematics.

### Step 3: Identify the Correct Answer
Based on the analysis, the correct answer is:
**Third option: Diversity of kinds of organisms and their relationship.**

### Conclusion
Systematics is primarily concerned with the classification of organisms based on their diversity and evolutionary relationships.

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