Zack is a high school student with a speech disorder. Which one of the following characteristics is least likely to be associated with his disability?
A. Zack sometimes says sentences with the words in an atypical order.
B. Zack's reading skills are among the lowest in his class.
C. When asked to speak in front of a group, Zack blushes and looks uncomfortable.
D. Zack has difficulty with writing assignments.