Which of the following is Sewall Wright effect?

Options

A. Gene pool
B. Genetic drift
C. Gene migration
D. Natural selection.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the definition or identification of the Sewall Wright effect among the provided options.

2. **Identify the Options**: The options given are:
- 1st: Gene pool
- 2nd: Genetic drift
- 3rd: Gene migration
- 4th: Natural selection

3. **Research Sewall Wright**: Sewall Wright was a prominent geneticist known for his work on population genetics. One of his key contributions is the concept of genetic drift.

4. **Define Genetic Drift**: Genetic drift refers to the random changes in allele frequencies within a population. This can occur due to various factors such as mutations, environmental changes, or random sampling effects.

5. **Connect Genetic Drift to Sewall Wright Effect**: The Sewall Wright effect is another term for genetic drift. It emphasizes the impact of chance events on the genetic composition of a population.

6. **Select the Correct Answer**: Based on the understanding that the Sewall Wright effect is synonymous with genetic drift, the correct answer to the question is option 2: Genetic drift.

**Final Answer**: The Sewall Wright effect is best described as genetic drift.

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