The rate at which new born individuals are joining the population by reproduction is known as

Options

A. natality
B. mortality
C. Fertiliy
D. Vitality

Answer

To solve the question regarding the rate at which new born individuals are joining the population by reproduction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**: We need to analyze the terms provided in the options: Natality, Mortality, Fertility, and Vitality.

2. **Defining Natality**: Natality refers to the number of births in a population over a specific period. It indicates how many new individuals are being added to the population through reproduction.

3. **Defining Mortality**: Mortality is the opposite of natality; it refers to the number of deaths in a population over a specific period. This does not relate to the addition of new individuals.

4. **Defining Fertility**: Fertility refers to the natural capability of an organism to reproduce. While it is related to reproduction, it does not specifically measure the rate of new individuals joining the population.

5. **Defining Vitality**: Vitality refers to the capacity of an organism to grow, live, and develop. This term does not pertain to the rate of new births.

6. **Conclusion**: Given the definitions, the term that specifically measures the rate at which new born individuals are joining the population by reproduction is **Natality**.

### Final Answer:
The correct answer is **Natality**.

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