Density of population increases when________.

Options

A. Emigration increases
B. Immigration decreases
C. Mortality increase
D. Natality Increases

Answer

To solve the question "Density of population increases when________," we will analyze each option provided:

1. **Option 1: Emigration increases.**
- Emigration refers to the movement of individuals out of a population. If more individuals leave the population, the overall number of individuals in that population decreases, leading to a decrease in population density. Therefore, this option is incorrect.

2. **Option 2: Immigration decreases.**
- Immigration is the movement of individuals into a population. If immigration decreases, fewer individuals are entering the population. This would also lead to a decrease in population density, making this option incorrect as well.

3. **Option 3: Mortality increases.**
- Mortality refers to the death rate within a population. If mortality increases, more individuals are dying, which would lead to a decrease in the overall population size and thus a decrease in population density. Therefore, this option is also incorrect.

4. **Option 4: Natality increases.**
- Natality refers to the birth rate within a population. If natality increases, more individuals are being born into the population, which would lead to an increase in the overall population size and consequently an increase in population density. This option is correct.

**Conclusion:**
The correct answer is that the density of population increases when **natality increases** (Option 4).

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