The nurse is giving instructions to a clie
题型：单项选择题
问题：
The nurse is giving instructions to a client who is going home with a cast on his leg. Which point is most critical ？（）
A．Using crutches properly.
B．Exercising joints above and below the cast, as ordered.
C．Avoiding walking on a leg cast without the physician's permission.
D．Reporting signs of impaired circulation.