The term linguistic variation, or simply variation, refers to regional, social or contextual differences in the ways that a particular language is used. Since the rise of sociolinguistics in the 1960s, interest in linguistic variation also called linguistic variability, has developed rapidly. R. L. Trask notes “variation far from being peripheral and inconsequential, is a vital part of ordinary linguistic behavior”.

(Key Concepts in Language and Linguistics, 2007.)

Choose the alternative which is NOT consistent concerning linguistic variability.