The type of variable that can contaminate the results of an experiment and may be an alternative to a causal relationship is known as a(n):

The answer is extraneous variable
an extraneous variable is the type of variables that is impossible to control or properly predicted by the researchers.
For example, in researching life expectancy of a group of animals in a certain region, sudden extreme weather that killed a lot of the animals could be considered as an extraneous variable.

It gets more wisdom and they know more knowledge

Americans often speak of their country as one of several large regions.  these regions are cultural units rather than governmental units --  formed by history and geography and shaped by the economics, literature and folkways that all the parts of a region share. what makes one region different from another? a region's multicultural heritage as well as distinct demographic characteristics like age and occupation make regions different and special. within several regions, language is used differently and there are strong dialects. there are also differences in outlook and attitude based on geography.