The proponent of the theory of spontaneous generation was

Options

A. Louis Pasteur
B. van Helmont
C. Spallanzani
D. Francesco Redi

Answer

**Step-by-Step Solution:**

1. **Understanding the Theory of Spontaneous Generation**: The theory of spontaneous generation, also known as abiogenesis, suggests that life can arise from non-living matter. This concept was widely accepted before modern biology provided evidence against it.

2. **Identifying the Proponent**: The proponent of the theory of spontaneous generation is often attributed to various scientists, but in this context, it is specifically mentioned that Von Helmuth (likely a reference to John Needham, as the name might be a transcription error) is credited with supporting this idea through his experiments.

3. **Describing the Experiment**: Von Helmuth conducted an experiment where he placed a dirty shirt with some wheat. After a period of time, he claimed that mice were produced from this setup, which he interpreted as evidence supporting spontaneous generation.

4. **Contrasting Other Scientists**: It's important to note that other scientists, such as Francesco Redi and Lazzaro Spallanzani, conducted experiments that disproved the theory of spontaneous generation. Redi's work in the 17th century showed that maggots on meat came from eggs laid by flies, not from the meat itself. Spallanzani further demonstrated that microorganisms did not arise in sterilized broth unless exposed to air.

5. **Conclusion**: The correct answer to the question is that the proponent of the theory of spontaneous generation is Von Helmuth, who believed that life could originate from non-living matter.

**Final Answer**: The proponent of the theory of spontaneous generation was Von Helmuth.

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