Which of the following is false?

Options

A. In a population birth rate and death rate refer to per capita births and death respectively
B. The size of a population for any species is a static parameter
C. In nature, we rarely find isolated, single individuals of any species
D. Ecological effects of any factors on a population are generally reflected in its size `//` population density

Answer

To determine which statement is false, we will analyze each statement one by one.

### Step 1: Analyze the First Statement
The first statement claims that in a population, birth rate and death rate refer to per capita births and deaths respectively.
- **Evaluation**: This statement is true. Birth rate and death rate are indeed calculated per individual in the population, which means they are per capita measures.

### Step 2: Analyze the Second Statement
The second statement asserts that the size of a population for any species is a static parameter.
- **Evaluation**: This statement is false. The size of a population is not static; it can change over time due to various factors such as birth rates, death rates, immigration, and emigration. Populations can expand, decline, or remain stable.

### Step 3: Analyze the Third Statement
The third statement mentions that in nature, we rarely find isolated single individuals of any species.
- **Evaluation**: This statement is true. Most species are found in groups or populations rather than as isolated individuals.

### Step 4: Analyze the Fourth Statement
The fourth statement states that ecological effects of any factors on a population are generally reflected in its size and population density.
- **Evaluation**: This statement is also true. Changes in ecological factors can affect the size and density of a population.

### Conclusion
From the analysis, the false statement is the second one, which claims that the size of a population for any species is a static parameter.

### Final Answer
The false statement is: "The size of a population for any species is a static parameter."

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