The process by which individuals are included into a population is known as

Options

A. Immigration
B. Emigration
C. Migration
D. Both (a) and (b)

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process by which individuals are added to a population. This involves understanding the terms related to population dynamics.

2. **Identifying Key Terms**: The key terms to focus on are "immigration," "emigration," and "migration."
- **Immigration** refers to individuals moving into a population from another area.
- **Emigration** refers to individuals leaving a population to move to another area.
- **Migration** is a broader term that encompasses both immigration and emigration.

3. **Defining Immigration**: Immigration is specifically the process where organisms move into a new area, thereby increasing the population size of that area. This can happen for various reasons, such as searching for food, escaping unfavorable conditions, or seasonal changes.

4. **Examples of Immigration**:
- Grazing animals may migrate to find food during scarcity.
- Birds like flamingos migrate to warmer regions during winter months.

5. **Conclusion**: Based on the definitions and examples, the correct answer to the question is "immigration," as it specifically refers to the addition of individuals into a population.

**Final Answer**: The process by which individuals are included into a population is known as **immigration**.

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