Rueben (8;5 Years) Has Difficulty Clearly Articulating the // in His

Rueben (8;5 years) has difficulty clearly articulating the // in his name. He says [] instead of //. An articulation assessment revealed that Rueben derhotacized /11ee98b2_5efb_931f_a6de_437abf30e255_TB9704_11, 11ee98b2_71d3_a410_a6de_9fbc6db03d2a_TB9704_11, 11ee98b2_840e_ffd1_a6de_97f1a6068f3a_TB9704_11/. No other speech production errors were detected. Rueben has no prior history of speech, language or literacy difficulties. In light of these observations Rueben most likely has:

A) phonological impairment.
B) childhood dysarthria.
C) childhood apraxia of speech.
D) articulation impairment.