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Size of population can be decreased by -...

Size of population can be decreased by -

A

A higher birth rate

B

Immigration

C

Emigration

D

Increase in food availability

Text Solution

AI Generated Solution

The correct Answer is:
To determine how the size of a population can be decreased, we need to analyze the options provided: 1. **Higher Birth Rate**: A higher birth rate means more individuals are being born into the population, which would lead to an increase in population size. Therefore, this option does not contribute to a decrease in population size. 2. **Immigration**: Immigration refers to the movement of individuals into a population from another area. This influx of individuals would also lead to an increase in the population size. Thus, this option does not contribute to a decrease in population size. 3. **Emigration**: Emigration is the movement of individuals out of a population to another area. When individuals leave a population, the total number of individuals in that population decreases. Therefore, this option does contribute to a decrease in population size. 4. **Increase in Food Availability**: When food availability increases, it generally supports a larger population by providing the necessary resources for survival and reproduction. This would lead to an increase in population size, not a decrease. Based on the analysis above, the only option that leads to a decrease in population size is **Emigration**. **Final Answer**: The size of the population can be decreased by **Emigration**. ---
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