The percentage of ratio of natality over mortality is called :

Options

A. Vital index
B. Total count
C. Population density
D. none of these

Answer

To solve the question regarding the percentage of the ratio of natality over mortality, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Natality** refers to the birth rate, which is the number of live births in a given population during a specific time period.
- **Mortality** refers to the death rate, which is the number of deaths in a given population during a specific time period.

2. **Identify the Ratio**:
- The question asks for the ratio of natality to mortality. This can be expressed mathematically as:
\[ \text{Ratio} = \frac{\text{Natality}}{\text{Mortality}} \]

3. **Convert to Percentage**:
- To express this ratio as a percentage, we multiply by 100:
\[ \text{Percentage Ratio} = \left( \frac{\text{Natality}}{\text{Mortality}} \right) \times 100 \]

4. **Define the Term**:
- The term that describes the percentage of the ratio of natality over mortality is known as the **Vital Index**. This index provides insight into the health and growth of a population.

5. **Conclusion**:
- Therefore, the answer to the question is that the percentage of the ratio of natality over mortality is called the **Vital Index**.

### Final Answer:
The percentage of the ratio of natality over mortality is called the **Vital Index**.

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