After 5 days of hospitalization, the client who is receiving morphine sulfate for pain control asks for more pain medication with increasing frequency and exhibits increased anxiety and restlessness. His physical condition is stable. What is the probable cause of his behavior

A. His morphine dosage is too high.
B. His coping mechanisms are exhausted.
C. He is becoming addicted to the narcotic.
D. He has developed tolerance to his narcotic dosag

骨质增生由下述哪种原因引起（）

A.骨动脉或静脉栓塞及血栓形成

B.肿瘤组织形成的肿瘤骨

C.成骨细胞活动形成新生骨或软骨内成骨

D.软骨细胞活动形成新生骨

E.以上都不是