Ratio between mortality and natality is called

Options

A. Population ratio
B. Vital index
C. Density eoefficienl
D. Census ratio

Answer

To solve the question regarding the ratio between mortality and natality, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Natality**: This refers to the birth rate in a population, which is typically measured as the number of births per thousand individuals in a given time period.
- **Mortality**: This refers to the death rate in a population, which is measured as the number of deaths per thousand individuals in a given time period.

2. **Define the Ratio**:
- The ratio between mortality and natality can be expressed mathematically as:
\[ \text{Ratio} = \frac{\text{Mortality}}{\text{Natality}} \]

3. **Identify the Correct Term**:
- The question asks for the specific term used to describe the ratio between mortality and natality. From biological terminology, this ratio is referred to as the **Vital Index**.

4. **Formula for Vital Index**:
- The Vital Index can also be represented in a specific formula:
\[ \text{Vital Index} = \left( \frac{\text{Natality}}{\text{Mortality}} \right) \times 100 \]
- This formula helps in understanding the overall population dynamics by comparing the birth rate and death rate.

5. **Conclusion**:
- Based on the definitions and the understanding of the terms, we conclude that the ratio between mortality and natality is called the **Vital Index**.

### Final Answer:
The ratio between mortality and natality is called the **Vital Index**.

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