The critical minimum and maximum value of an evironmental factor is called

Options

A. Limiting factor
B. Law of minimum
C. Limits of tolerance
D. Carrying capacity

Answer

To answer the question, "The critical minimum and maximum value of an environmental factor is called," we need to analyze the options provided and understand the definitions of each term.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the term that describes the critical minimum and maximum values of an environmental factor.

2. **Analyzing the Options**:
- **Limiting Factor**: This term refers to a resource or environmental condition that limits the growth, abundance, or distribution of an organism or a population. However, it does not specifically refer to the minimum and maximum values.
- **Law of Minimum**: Proposed by Liebig, this law states that the growth of a population is determined by the scarcest resource (the limiting factor), not by the abundance of resources. Again, this does not directly address the minimum and maximum values.
- **Limits of Tolerance**: Proposed by Shelford, this concept refers to the range within which an organism can survive. It defines the minimum and maximum limits of environmental factors that affect the survival and abundance of organisms.
- **Carrying Capacity**: This term refers to the maximum population size that an environment can sustain indefinitely, given the food, habitat, water, and other necessities available in the environment. It does not specifically refer to the critical minimum and maximum values of environmental factors.

3. **Identifying the Correct Answer**: Based on the definitions, the term that best fits the description of "the critical minimum and maximum value of an environmental factor" is **Limits of Tolerance**.

### Final Answer:
The critical minimum and maximum value of an environmental factor is called **Limits of Tolerance**.

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