The nurse is planning care for a 10-year-old child in the acute phase of rheumatic fever. Which activity would be most appropriate for the nurse to schedule in the care plan ？（）

A．Playing ping-pong.

B．Reading books.

C．Climbing on play equipment in the playroom.

D．Unrestricted ambulation.

检验可以用于对两个相关总体平均数的差异评价。