Among the following, which theory was not connected with the origin of life?

Options

A. Big Bang theory
B. Theory of Panspermia
C. Theory of spontaneous generation
D. Theory of chemical evolution

Answer

To determine which theory is not connected with the origin of life, we will analyze the provided options one by one.

### Step-by-Step Solution:

1. **Identify the Theories**: We need to look at the theories mentioned in the question. The options include:
- Big Bang Theory
- Theory of Panspermia
- Theory of Spontaneous Generation
- Theory of Chemical Evolution

2. **Understand Each Theory**:
- **Big Bang Theory**: This theory explains the origin of the universe, stating that it began from a single massive explosion and has been expanding ever since. It does not specifically address how life originated.
- **Theory of Panspermia**: This theory suggests that life did not originate on Earth but was brought here from other planets or celestial bodies.
- **Theory of Spontaneous Generation**: This theory posits that life can arise from non-living matter, such as how maggots were once thought to arise from decaying meat.
- **Theory of Chemical Evolution**: This theory proposes that life began through a series of chemical reactions that led to the formation of complex organic molecules from simpler inorganic compounds.

3. **Determine Relevance to Origin of Life**:
- The Big Bang Theory is focused on the universe's origin and does not deal with how life started.
- The other three theories (Panspermia, Spontaneous Generation, and Chemical Evolution) are all concerned with the origin of life on Earth.

4. **Conclusion**: Since the Big Bang Theory does not relate to the origin of life, it is the correct answer to the question.

### Final Answer:
The theory that is not connected with the origin of life is the **Big Bang Theory**.

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