Explanation:
b) Writing
Anthropologists and linguists preserve languages by writing them. This involves documenting the vocabulary, grammar, syntax, and other linguistic elements of a language in written form. By recording languages in writing, researchers can create dictionaries, grammar books, and other resources that help to document and study languages. Writing also allows languages to be preserved for future generations, even if the spoken form becomes endangered or extinct. Additionally, written materials can be used to teach languages to new learners and to promote language revitalization efforts. Overall, writing plays a crucial role in the preservation and study of languages by providing a tangible record that can be accessed and analyzed over time.