Because most human characteristics are complex, many genes act together to determine a trait. this is called:

The correct answer is - Polygenic inheritance.

Explanation:

Polymeric inheritance takes place if a trait is influenced by two or more genes at a time. The genes can be normally high in numbers but show minute influences in the particular trait.

In humans, there are many complex gene interactions that control different characters of traits such as hair color, eye color, the height of individuals, and weight or skin color. There are many more traits that show polygenic inheritance.

Thus, the correct answer is - polygenic inheritance.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.