The earliest attempt to the scientific basis for classification is made by

Options

A. Linnaeus
B. Whittaker
C. Aristotle
D. Theophrastus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the earliest attempt to establish a scientific basis for classification in biology.

2. **Identifying Key Figures in Classification**:
- **Aristotle**: Known for his early classification of living organisms based on morphological characteristics.
- **Linnaeus**: Developed the two-kingdom classification system, classifying organisms into Plantae and Animalia.
- **Whittaker**: Proposed the five-kingdom classification system, which included Monera, Protista, Fungi, Plantae, and Animalia.
- **Theophrastus**: Known for his work in botany but not specifically for classification systems.

3. **Analyzing Aristotle's Contributions**:
- Aristotle classified animals based on the presence or absence of red blood cells (RBCs).
- He also categorized plants into groups such as trees, shrubs, and herbs based on their morphological traits.

4. **Comparing Other Contributors**:
- Linnaeus's classification was significant but came after Aristotle.
- Whittaker's five-kingdom system is more advanced and also came later.
- Theophrastus, while influential in botany, did not contribute significantly to classification systems.

5. **Conclusion**: Based on the analysis, the earliest attempt to establish a scientific basis for classification is attributed to Aristotle.

**Final Answer**: The correct answer is Aristotle.

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