Question

The unit of natural selection is
A. Family
B. Species
C. Individual
D. Population

Answer 1

Hint: Natural selection is a process that results in the adaptation of an organism to its environment through selectively reproducing changes in its genetic constitution. Natural selection favours an organism for the differential survival and reproduction of individuals due to variation. In a subsequent generation, these heritable changes are passed and work as a mechanism in evolution.

Complete answer:
A British naturalist, Charles Darwin had proposed the theory of biological evolution by natural selection.
Natural selection is gradual, a nonrandom process by which traits or characteristics of an organism become either more or less common.
In natural selection, significant advantageous variations occurred in the genetic constitution or genotype that increases chances of an organism for survival and reproduction are preserved and proliferated from generation to generation at the cost of less advantageous variations.
Natural selection makes the populations to get adapted, more well-suited, to their environments over time. Natural selection is phenomena that totally depends on the environment and so needs existing heritable variation in a population. This suggests that the unit of natural selection is individual as the genetic constitution works at an individual level.

So, the correct answer is option C.

Note:
Darwin's theory of natural selection in evolution is based on the significant rate of reproduction in organisms, the struggle for existence and survival of the fittest. Natural selection is a certain outcome of the following three principles:
> Most of the characteristics of an organism are inherited.
> More offspring are produced than can survive.
> The offspring with more favourable characteristics will only survive and reproduce.