यह अवधारणा कि भाषाओं में विविधताएँ और अंतर होते हैं, निम्नलिखित में से मुख्य रूप से किसके भाषाई सिद्धांतों से संबंधित है?

In the field of linguistics, scholars often distinguish between descriptive and prescriptive approaches to the study of language. Which of the following statements best characterizes descriptive linguistics as practiced by modern linguists?

Which statement is true in relation to the linguistic concept of 'code-switching'?