The recapitulation theory means that:

Options

A. All organisms start as an egg
B. Life history of an organism reflects its evolutionary history
C. Non living matters form life
D. Progeny resembles parents

Answer

**Step-by-Step Solution:**

1. **Understanding Recapitulation Theory**: The recapitulation theory, famously summarized by the phrase "ontogeny recapitulates phylogeny," suggests that the development (ontogeny) of an individual organism reflects the evolutionary history (phylogeny) of that organism's species.

2. **Origin of the Theory**: This theory was proposed by Ernst Haeckel, a German biologist, in the 19th century. He believed that as an organism develops from an embryo to an adult, it goes through stages that resemble the adult forms of its evolutionary ancestors.

3. **Analyzing the Options**:
- **Option A**: "All organisms start as an egg" - This is not a comprehensive definition of recapitulation theory.
- **Option B**: "Life history of an organism reflects its evolutionary history" - This aligns with the essence of recapitulation theory.
- **Option C**: "Non-living matters form life" - This is related to abiogenesis, not recapitulation.
- **Option D**: "Progeny resembles parents" - While this is true in a general sense, it does not capture the specific idea of recapitulation.

4. **Conclusion**: Based on the analysis, the correct interpretation of the recapitulation theory is that "the life history of an organism reflects its evolutionary history." This means that as an organism develops, it goes through stages that mirror the evolutionary changes its species has undergone.

**Final Answer**: The recapitulation theory means that the life history of an organism reflects its evolutionary history.

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