Final answer:
The farmer selectively breeding cotton plants to produce deep-green cotton demonstrates artificial selection, which is similar to natural selection but involves human intervention. Both are forms of evolutionary change, underlining the concept of evolution through the alteration of trait frequency in a population over time.The correct option is A.
Step-by-step explanation:
The example of the farmer selectively breeding cotton plants to produce a deep-green cotton is an instance of artificial selection. This is similar to natural selection, where individuals with favorable traits tend to survive and reproduce, passing on these traits to future generations.
In artificial selection, however, it is humans rather than nature that select the traits they find most useful or attractive. By selecting the cotton plants with a greenish hue for breeding, the farmer is able to influence and accelerate the expression of this trait in the cotton population.
Both forms of selection show how the frequency of certain traits in a population can change over time, providing evidence for the concept of evolution.
The green cotton case thus serves as an example of how human intervention can direct the course of evolutionary change in species through selective breeding.The correct answer is option A.