What is the term for a grammar model that uses a tree structure to describe phrases as constituent parts?

• A. A tree structure that describes phrases as constituent grammatical parts
• B. A set of phonology rules
• C. A collection of dialect variations
• D. A historical model of syntax

Answer: (A)

Understanding how grammar can be represented as a hierarchical tree that shows phrases as units is the idea behind this. This approach is called phrase structure grammar, also known as constituent structure grammar. It uses tree diagrams to break sentences into constituents like noun phrases and verb phrases, showing how the whole sentence is built from smaller parts. The other options don’t fit because they refer to sounds (phonology), regional language differences (dialects), or older theoretical ideas about syntax rather than a tree-based way to represent phrase structure. So the term described is phrase structure grammar.