Change with descent it the basis of which theory :

Options

A. Recapitulation theory
B. Oparin's theory
C. Theory of organic evolution
D. Cell theory

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks which theory is based on the concept of "change with descent." This implies a focus on how species evolve over time through the passing of traits from one generation to the next.

2. **Analyzing the Options:**
- **Recapitulation Theory:** This theory suggests that the development of an individual organism (ontogeny) follows the same progression as the evolutionary history of that organism's species (phylogeny). It does not primarily focus on descent with modification.
- **Opt-in Theory:** This is not a widely recognized theory in biology related to evolution or descent.
- **Theory of Organic Evolution:** This theory, often associated with Charles Darwin, emphasizes that species change over time through processes such as natural selection and genetic mutation, which aligns with the concept of descent with modification.
- **Cell Theory:** This theory states that all living organisms are composed of cells and that the cell is the basic unit of life. It does not pertain to evolutionary changes over time.

3. **Identifying the Correct Answer:** Given the definitions and implications of each option, the "theory of organic evolution" is the one that directly relates to the concept of change with descent. This theory explains how traits are inherited and modified over generations, leading to the evolution of species.

4. **Conclusion:** Therefore, the correct answer to the question is **option C: the theory of organic evolution**.

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