The measure of maximum rate of reproduction under optimal condition is known as :

Options

A. ultimate level
B. carrying capacity
C. nataclity
D. biotic potential

Answer

To solve the question regarding the measure of maximum rate of reproduction under optimal conditions, we will analyze the given options one by one.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the maximum rate of reproduction that an organism can achieve when environmental conditions are ideal.

2. **Analyzing the Options**:
- **Ultimate Level**: This term does not have a specific meaning in biology regarding reproduction. It suggests a final limit, which is not applicable in this context. Therefore, this option is incorrect.

- **Carrying Capacity**: This refers to the maximum number of individuals of a particular species that an environment can support sustainably. It is not directly related to the maximum reproductive rate, so this option is also incorrect.

- **Natality**: This term refers to the birth rate of a population, indicating how many individuals are born over a specific period. While it relates to reproduction, it does not specifically denote the maximum potential under optimal conditions. Thus, this option is incorrect as well.

- **Biotic Potential**: This term specifically refers to the maximum reproductive capacity of an organism under optimal environmental conditions. It indicates how many offspring an organism can produce if resources are unlimited. This is the correct answer.

3. **Conclusion**: After analyzing all the options, the correct answer to the question is **Biotic Potential**.

### Final Answer:
The measure of maximum rate of reproduction under optimal conditions is known as **Biotic Potential**.

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