Which of the following factors help in evolution but is considerd the basic factor for evolution :

Options

A. Isolation
B. Adaptation
C. Variation
D. Mutation

Answer

**Step-by-Step Solution:**

1. **Understanding Evolution**: Evolution refers to the process through which species change over time through various mechanisms. It is important to identify which factors are fundamental to this process.

2. **Identifying the Options**: The options provided are:
- Isolation
- Adaptation
- Variation
- Mutation

3. **Analyzing Each Option**:
- **Isolation**: This refers to the separation of organisms of the same species due to geographical or environmental barriers. While it can lead to speciation, it is not considered the basic factor for evolution.
- **Adaptation**: This is the process by which organisms adjust to their environment to enhance their survival and reproduction. According to Charles Darwin's Natural Selection Theory, adaptation is a key factor in evolution and is considered the basic factor.
- **Variation**: This refers to the differences among individuals within a species. While variation is important for natural selection to act upon, it is not the basic factor itself.
- **Mutation**: This is a change in the genetic material of an organism. Mutations can introduce new traits into a population, but they are not the fundamental factor driving evolution.

4. **Conclusion**: After analyzing the options, adaptation is identified as the correct answer since it is considered the basic factor for evolution according to Darwin's theory.

**Final Answer**: The correct answer is **B) Adaptation**.

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