Louis Pasteur by careful experimentation demonstrated that/the

Options

A. Phenomenon of chemical evolution
B. There is spontaneous genration of life
C. Life comes form pre-existing life
D. Abiogenic origin of life

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about Louis Pasteur's experiments and what he demonstrated through them.

2. **Identifying the Options**: The options provided are:
- A) Phenomenon of chemical evolution
- B) Spontaneous generation of life
- C) Life comes from pre-existing life
- D) Biogenic origin of life

3. **Analyzing Pasteur's Contribution**: Louis Pasteur is known for his experiments that disproved the theory of spontaneous generation, which suggested that life could arise from non-living matter. Instead, he demonstrated that life comes from pre-existing life.

4. **Describing Pasteur's Experiment**: Pasteur conducted an experiment using two types of flasks:
- One flask was sterilized and sealed, preventing any microorganisms from entering.
- The other flask was open to the air. Both flasks contained pieces of meat.

5. **Observing the Results**:
- In the sterilized flask, no microbial growth occurred, indicating that no life emerged from the meat.
- In the open flask, microorganisms grew, showing that they came from the environment, not from the meat itself.

6. **Conclusion**: Based on his experiments, Pasteur concluded that life does not spontaneously arise from non-living matter but comes from pre-existing life. Therefore, the correct answer to the question is that Louis Pasteur demonstrated that life comes from pre-existing life.

**Final Answer**: C) Life comes from pre-existing life.

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