Which condition is characterized by difficulty retrieving words and constructing grammatically correct sentences?

Broca aphasia is a specific type of language disorder that occurs due to damage to the Broca's area in the brain, which is responsible for speech production and language processing. Individuals with Broca aphasia struggle primarily with expressing themselves verbally. They often have difficulty retrieving words and constructing grammatically correct sentences, which can result in speech that is slow and laborious. While their understanding of language may remain relatively intact, their ability to form fluent sentences is impaired. This aligns perfectly with the characteristics outlined in the question, making Broca aphasia the correct answer.

In contrast, Wernicke aphasia involves fluent but nonsensical speech and significant trouble with comprehension, rather than problems with producing coherent sentences. Aphasia is a broader term that encompasses various types of language impairments, not specifically the retrieval and grammatical issues focused on here. An articulation disorder typically refers to difficulties in physically producing speech sounds rather than challenges with sentence structure or word retrieval.