The recapitulation theory was put forth by

Options

A. A.Haeckel
B. B.Cuvier
C. C.Wallace
D. D.Lamarck

Answer

**Step-by-Step Solution:**

1. **Identify the Theory**: The question asks about the recapitulation theory, which is a significant concept in biology related to development and evolution.

2. **Research the Origin**: The recapitulation theory is known to have been proposed by a scientist.

3. **Name the Scientist**: The theory was put forth by Ernst Haeckel in the 1860s.

4. **Understand the Theory**: Haeckel's recapitulation theory, also known as the Biogenetic law, suggests that the development of an embryo (embryogenesis) goes through stages that resemble the adult forms of its evolutionary ancestors.

5. **Select the Correct Option**: Based on the information, the correct answer to the question is Ernst Haeckel.

**Final Answer**: The recapitulation theory was put forth by Ernst Haeckel.

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