One major criticism of Darwin's theory is that :

Options

A. It presumes that environment upon earth has been changing
through gas
B. It does not explain variations with heredity
C. It overestimates reproductive capacity of animals and plants
D. It does not explain vestigial organs

Answer

**Step-by-Step Solution:**

1. **Understanding Darwin's Theory**:
- Darwin's theory, known as Darwinism, is based on the concept of natural selection. It posits that species evolve over time through the process of adaptation to their environment. Organisms that are better adapted to their environment tend to survive and reproduce, passing on their advantageous traits to the next generation.

2. **Identifying Criticisms**:
- Despite its foundational role in evolutionary biology, Darwin's theory has faced several criticisms. These criticisms often focus on aspects that Darwin did not fully explain or account for in his theory.

3. **Evaluating the Options**:
- The question provides several options regarding criticisms of Darwin's theory:
- It presumes that the environment upon earth has been changing through gas.
- It does not explain variation with heredity.
- It overestimates reproductive capacity of animals and plants.
- It does not explain the vestigial organ.

4. **Analyzing Each Option**:
- **Option 1**: "It presumes that the environment upon earth has been changing through gas."
- This is not a major criticism of Darwin's theory.
- **Option 2**: "It does not explain variation with heredity."
- This is a significant criticism, as Darwin did not have a clear understanding of the mechanisms of heredity (which were later explained by genetics).
- **Option 3**: "It overestimates reproductive capacity of animals and plants."
- This is also not a major criticism; Darwin acknowledged that not all offspring survive.
- **Option 4**: "It does not explain the vestigial organ."
- While Darwin mentioned vestigial organs, he did not provide a comprehensive explanation for their existence.

5. **Conclusion**:
- The major criticism of Darwin's theory is that it does not adequately explain variation with heredity. This limitation became clearer with the development of genetics, which provided a better understanding of how traits are inherited.

**Final Answer**: The major criticism of Darwin's theory is that it does not explain variation with heredity.

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