Which function is most affected by expressive aphasia?

Expressive aphasia, often resulting from damage to Broca's area in the left frontal lobe of the brain, primarily impacts an individual's ability to produce language effectively. This condition is characterized by difficulty in formulating coherent speech and writing, even though comprehension of spoken and written language may remain relatively intact.

As a result, when individuals attempt to express themselves, they may struggle to find the right words, construct grammatically correct sentences, or articulate their thoughts in a clear and organized manner. This difficulty does not stem from a lack of understanding or cognitive function, but rather from challenges associated specifically with speech production and language formulation. Therefore, the formulation of speech and writing is the primary function affected by expressive aphasia, making it the most relevant choice in this context.