[dr.Ira]

A 6-year-old boy is brought to the office by his parents who are concerned because he has been refusing to use his left arm for 1 day. The parents report that he has been in good health and has not suffered any recent falls or injuries to the arm that they are aware of. The father does recall one incident 2 days ago when he pulled upward on the boy's right arm to prevent him from tripping as they descended a flight of stairs. The boy is holding his right arm with the elbow flexed and the forearm pronated. He begins to cry when you attempt to examine the arm. The most appropriate next step is
A. closed reduction and cast immobilization
B. a CT of the right arm
C. measurement of compartment pressure of the forearm
D. supination of the forearm with the elbow flexed
E. a trial of compressive bandage on the right arm