Believers of spontaneous generation theory believed that :

Options

A. Life originated from other similar organisms or spontaneously
B. Life originated only spontaneously
C. Life originated from similar organisms
D. Life originated from air

Answer

### Step-by-Step Text Solution:

1. **Understanding Spontaneous Generation Theory**: The spontaneous generation theory posits that life can arise from non-living matter without any biological parent. This concept was widely accepted before modern biology provided a clearer understanding of the origins of life.

2. **Historical Context**: The theory was notably proposed by Aristotle, a prominent philosopher and scientist in ancient Greece. He suggested that certain life forms could emerge spontaneously from their environment.

3. **Examples Provided by Aristotle**: Aristotle provided examples such as:
- Fleas arising from dust.
- Maggots appearing from decaying meat.
- Tapeworms originating from their hosts.

4. **Core Belief of the Theory**: The fundamental belief of the spontaneous generation theory is that life originated spontaneously from non-living matter, without the need for pre-existing life forms.

5. **Rejection of the Theory**: Over time, the spontaneous generation theory was challenged and ultimately rejected by the scientific community. This was due to advancements in biological understanding and experimentation that demonstrated life does not arise from non-living matter.

6. **Alternative Theories**: The rejection of spontaneous generation led to the acceptance of alternative theories, such as the theory of chemical evolution, proposed by scientists like Oparin and Haldane, which suggests that life originated from a series of chemical reactions in primordial conditions.

### Final Answer:
Believers of spontaneous generation theory believed that life originated spontaneously from non-living matter.

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