Which term refers to the arrangement of words and phrases to form well-structured sentences in a language?

The correct term that refers to the arrangement of words and phrases to form well-structured sentences in a language is syntax. Syntax is a fundamental aspect of grammar that dictates how different parts of speech (nouns, verbs, adjectives, etc.) are combined to create meaningful sentences. Understanding syntax allows speakers and writers to construct clear and coherent sentences that adhere to the rules of a language.

In contrast, semantics deals with the meaning of words and sentences, focusing on how meaning is constructed and interpreted. Pragmatics is concerned with the use of language in social contexts, including the nuances of meaning that arise from situational factors. Metalinguistics involves the awareness and analysis of the properties and functions of language itself, including discussions about language structure and use, but it does not specifically address the arrangement of words and phrases into sentences. Thus, syntax is the specific term that encapsulates the concept of sentence structure within a language.