Which of the following will decrease the density of population in a given area ?

Options

A. Natrility and Immigration
B. Mortality and Immigration
C. Natality and Emigration
D. Mortality and Emigration

Explanation

To determine which factors will decrease the density of a population in a given area, we need to analyze the concepts of natality, mortality, immigration, and emigration. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the terms
- **Natality**: This refers to the birth rate in a population, which increases population density.
- **Mortality**: This refers to the death rate in a population, which decreases population density.
- **Immigration**: This refers to individuals moving into a population from outside, which increases population density.
- **Emigration**: This refers to individuals leaving a population to move elsewhere, which decreases population density.

### Step 2: Identify factors that decrease population density
- From the definitions:
- **Mortality** decreases population density because it indicates the number of deaths in the population.
- **Emigration** decreases population density because it indicates the number of individuals leaving the population.

### Step 3: Conclusion
- The two factors that will decrease the density of a population in a given area are **Mortality** and **Emigration**.

### Final Answer
The correct answer is: **Mortality and Emigration**.

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