According to the theory of evolution by natural selection:

A. Only traits for which we are aware of their advantage survive.
B. Only traits that provide an adaptive advantage spread through the population.
C. Giraffes that stretch their necks in reaching for food develop longer necks and pass that trait onto their offspring.
D. Test-taking was not one of the adaptive traits of the caveman.
E. Traits that have evolved will be expressed phenotypically regardless of the environment they are in.

Natural selection is a fundamental concept in evolution, favoring traits that enhance survival and reproduction. The example of long-necked giraffes illustrates how advantageous traits spread through populations over time.

Explanation:

Natural selection is a key mechanism in evolution that operates on heritable traits within a population. The process involves the selection of advantageous traits that increase an individual's ability to survive and reproduce.

For example, long-necked giraffes had an advantage in reaching high leaves for food, allowing them to survive and reproduce more than short-necked giraffes. Over time, this led to the spread of the long-neck trait in the giraffe population.

Natural selection is driven by factors such as differential survival and reproduction, where individuals with adaptive traits are more likely to pass on those traits to the next generation, resulting in gradual changes in the population.

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