Rate of natural increase' is :

Options

A. r
B. k
C. b
D. d

Answer

To answer the question "Rate of natural increase' is:", we need to clarify what the term means in the context of population biology.

### Step-by-Step Solution:

1. **Definition of Rate of Natural Increase**: The rate of natural increase (RNI) is defined as the difference between the birth rate and the death rate in a population over a specific period of time. It is usually expressed as a percentage.

2. **Formula**: The formula for calculating the rate of natural increase can be expressed as:
\[ RNI = (Birth Rate - Death Rate) \]
where:
- Birth Rate is the number of live births per 1,000 people per year.
- Death Rate is the number of deaths per 1,000 people per year.

3. **Understanding the Components**:
- **Birth Rate**: This is the rate at which new individuals are added to the population through reproduction.
- **Death Rate**: This is the rate at which individuals are removed from the population due to mortality.

4. **Significance of RNI**: The rate of natural increase is a crucial indicator of population growth. A positive RNI indicates that the population is growing, while a negative RNI indicates that the population is declining.

5. **Context of Logistic Growth**: In the context of logistic growth, the rate of natural increase (r) is influenced by environmental factors and resource availability, which can limit population growth as it approaches the carrying capacity (K) of the environment.

### Conclusion:
The rate of natural increase (RNI) is a measure of how fast a population is growing or declining based on the difference between birth and death rates.

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