Theory of evolution is mainly concernd with :

Options

A. Spontaneous generation
B. Theory of special creation
C. Gradual change
D. Condition of enviromnent

Answer

**Step-by-Step Solution:**

1. **Understanding the Theory of Evolution**: The theory of evolution primarily explains how species change over time through gradual processes. It was famously proposed by Charles Darwin.

2. **Key Concept - Natural Selection**: One of the main ideas of Darwin's theory is natural selection, which is often summarized by the phrase "survival of the fittest." This concept indicates that individuals better adapted to their environment are more likely to survive and reproduce.

3. **Evaluating the Options**:
- **Option A: Spontaneous Generation**: This theory suggests that life can arise from non-living matter, which is not related to Darwin's theory of evolution. Thus, this option is incorrect.
- **Option B: Theory of Special Creation**: This theory posits that species were created in their current forms and does not account for gradual changes over time. Therefore, this option is also incorrect.
- **Option C: Gradual Change**: This option aligns with the core of Darwin's theory, which emphasizes that evolution occurs through gradual changes over long periods. This is the correct answer.
- **Option D: Condition of Environment**: While the environment plays a role in natural selection, the theory itself focuses more on the gradual changes in species rather than the conditions of the environment alone. Hence, this option is incorrect.

4. **Conclusion**: After evaluating all the options, the correct answer to the question "Theory of evolution is mainly concerned with" is **Gradual Change**.

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