Final answer:
Traits like skin and hair color are an example of polygenic inheritance, where multiple genes contribute to a single trait, creating continuous variation and a range of phenotypes between extremes.Thus the correct option 3.
Step-by-step explanation:
The type of inheritance exhibited by traits such as skin and hair color, where genetic information is mixed and is not separated in future generations, is called polygenic inheritance. This form of inheritance involves the action of multiple genes contributing to a trait, resulting in continuous variation. Unlike the blending theory of inheritance that was thought to explain this before Mendel's research, we know these traits are not a blend where original traits are lost, but are due to the combined effects of several genes.
For example, skin color is a polygenic trait because it is determined by the cumulative effect of several genes, leading to a wide range of possible skin colors. Similarly, height is also polygenic, exhibiting a variety of phenotypes far more complex than what can be described by simple Mendelian genetics. Continuous variation is a hallmark of polygenic traits, where individuals can exhibit a range of phenotypes between two extremes.