inherited trait that makes an organism more fit in its current abiotic and biotic environment that has arisen as the result of the direct action of natural selection for its primary function is known as a/an what?

Adaptation

Explanation:

An adaptation can be described as any characteristic possessed by an organism which makes the organism better to survive in an environment. Natural selection tends to favour those organisms which have better adaptations or characteristics to survive in an environment. Such adaptations allow the organism to survive and pass on their characteristics to their offsprings. As a result, the allele frequency for this particular trait increases in the population.