If life come out of decaying and rotting matter like straw, mud etc. This was the theory of

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the theory that suggests life originates from decaying and rotting matter such as straw and mud.

2. **Identifying the Theory**: The theory that proposes life arises spontaneously from non-living matter is known as "spontaneous generation."

3. **Historical Context**: This theory was widely accepted by early philosophers and scientists, including notable figures like Thales, Plato, and Aristotle. They believed that life could emerge from non-living substances.

4. **Examples from History**: In ancient Egypt, it was believed that the mud from the Nile could spontaneously generate frogs, toads, snakes, and even crocodiles when warmed by the sun. Additionally, the philosopher Anaximander suggested that human sweat and wet grains could lead to the emergence of organisms.

5. **Conclusion**: Therefore, the answer to the question is that the theory which states that life comes from decaying and rotting matter is the theory of spontaneous generation.

**Final Answer**: The theory is known as spontaneous generation.

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