Unrestricted reproductive capacity is :

Options

A. Carrying capacity
B. Fertility
C. Birth rate
D. Biotic potential

Explanation

**Step-by-Step Solution:**

1. **Understanding Unrestricted Reproductive Capacity**:
- Unrestricted reproductive capacity refers to the maximum potential of an organism to reproduce under ideal environmental conditions, without any limitations such as food, space, or predation.

2. **Identifying Related Terms**:
- The terms related to reproductive capacity include:
- **Carrying Capacity**: The maximum number of individuals that an environment can sustain.
- **Fertility Rate**: The number of live births per 1000 women of childbearing age in a year.
- **Birth Rate**: The number of offspring produced per female per unit time.

3. **Differentiating Biotic Potential**:
- Biotic potential is defined as the physiological capacity of an organism to reproduce. It represents the maximum reproductive output of an organism under ideal conditions.

4. **Conclusion**:
- Among the terms discussed, the one that best describes unrestricted reproductive capacity is **Biotic Potential**. This is because it reflects the inherent ability of an organism to reproduce without environmental constraints.

**Final Answer**: Unrestricted reproductive capacity is best described as **Biotic Potential**.

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